Liquid container having liquid consumption detecing device

ABSTRACT

A liquid container, comprising: a housing containing therein liquid; a liquid supply opening formed in the housing for withdrawing the liquid from the housing; a liquid sensor mounted on the housing for detecting a level of the liquid which is variable in accordance with a consumption of the liquid; and a first partition wall extending in an interior of the housing and defining the interior of the housing into at least two liquid accommodating chambers which communicate with each other, the liquid accommodating chambers comprising: an air-communication side liquid accommodating chamber which communicates with ambient air; and a detection side liquid accommodating chamber in which the liquid sensor is disposed at an upper portion thereof.

This is a divisional of Application Ser. No. 10/243,730 filed Sep. 16,2002, which in turn is a divisional of Application Ser. No. 09/574,012filed May 19, 2000 now U.S. Pat. No. 6,536,861, the disclosures of whichare incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a liquid container equipped with apiezoelectric apparatus therein which detects the consumption state ofliquid inside a liquid container which houses the liquid. Moreparticularly, the present invention relates to the liquid containerequipped with a piezoelectric apparatus that detects liquid consumptionstatus in a liquid container which provides liquid to a recording headof an ink-jet recording apparatus.

2. Description of the Related Art

An ink cartridge mounted on an ink-jet type recording apparatus is takenas an example of a liquid container and is described below. In general,an ink-jet recording apparatus comprises: a carriage equipped with anink-jet type recording head comprised of a pressure generating meanswhich compresses a pressure generating chamber and a nozzle openingwhich discharges the compressed ink from a nozzle opening in the form ofink droplets; and an ink tank which houses ink supplied to the recordinghead through a passage, and is structured such that the printingoperation can be performed continuously. In general, the ink tank isstructured as a cartridge that can be detached from the recordingapparatus, so that a user can easily replace it at the time when the inkis used up.

Conventionally, as a method of controlling the ink consumption of theink cartridge, a method is known of controlling the ink consumption bymeans of a calculation in which the counted number of ink dropletsdischarged by the recording head and the amount of ink sucked in amaintenance process of the printing head are integrated by software, andanother method of controlling the ink consumption in which the time atwhich the ink is actually consumed is detected by directly mounting tothe ink cartridge two electrodes for use in detecting the liquidsurface, and so forth.

However, in the calculation-based method of controlling the inkconsumption by integrating the discharged number of ink droplets and theamount of ink or the like by the software, the pressure inside the inkcartridge and the viscosity of the ink change depending on usageenvironment such as ambient temperature and humidity, elapsed time afteran ink cartridge has been opened for use, and usage frequency at a userside. Thus, a problem is caused where a considerable error occursbetween the calculated ink consumption and the actual ink consumption.Moreover, another problem is caused in which the actual amount of inkremaining is not known because once the same cartridge is removed andthen mounted again, the integrated counted value is reset.

On the other hand, in the method of controlling by electrodes the timeat which the ink is consumed, the remaining amount of ink can becontrolled with high reliability since the actual ink consumption can bedetected at one point. However, in order that the liquid surface of theink can be detected, the ink need be conductive, so suitable types ofink for use are very limited. Moreover, a problem is caused in that afluid-tight structure between the electrodes and the cartridge might becomplicated. Moreover, since precious metal is usually used as theelectrode material, which is highly conductive and erosive,manufacturing costs of the ink cartridge increases thereby. Moreover,since it is necessary to attach the two electrodes to two separatepositions of the ink cartridge, the manufacturing process increases,thus causing a problem which increases the manufacturing costs.

Moreover, when managing the ink consumption status by mounting apiezoelectric device on the ink cartridge, ink inside the ink cartridgemay roll or bubble by the scanning of the ink cartridge during theprinting operation. By the waving or bubbling of ink nearby thepiezoelectric device, ink or bubble of ink attaches to the piezoelectricdevice. Then, there is a cases arises that the piezoelectric devicecannot detect the ink consumption quantity by the ink or bubble of inkattached to the piezoelectric device. In other words, even there is onlysmall amount of ink inside the ink cartridge, if the ink attaches to thepiezoelectric device mistakenly by the waving of ink, there is a dangerthat the piezoelectric device detects mistakenly that there is stillenough ink inside the ink cartridge. Moreover, if the bubble attaches tothe piezoelectric device, there is danger that the piezoelectric devicedetects mistakenly that there is no ink inside the ink cartridge even ifthe ink cartridge 180 is filled by ink.

Furthermore, there is problem that the position of mounting thepiezoelectric device on the ink cartridge is limited for detecting theink end status inside the ink cartridge. For example, if mounting thepiezoelectric device on the wall at the lower side of the ink surface,the piezoelectric device can detect the ink end. On the other hand, ifmounting the piezoelectric device on the wall at the upper side of theink surface, the piezoelectric device cannot detect the ink end.

SUMMARY OF THE INVENTION

Therefore, it is an object of the present invention to provide a liquidcontainer capable of reliably detecting a liquid consumption status anddispensing with a complicated sealing structure.

Moreover, it is another object of the present invention to prevent thewaving or bubbling of liquid around the piezoelectric device inside theliquid container.

Furthermore, it is still another object of the present invention toprovide a liquid container, the piezoelectric device of which canreliably detect a liquid consumption status by detecting the liquidsurface even in the case that liquid inside the liquid container rollsand bubbles.

Furthermore, it is still another object of the present invention toprovide a liquid container, the piezoelectric device of which canreliably detect a liquid consumption status even in the case that theliquid container tilts or fell down because the gas does not contactswith the piezoelectric device.

Furthermore, it is still another object of the present invention toprovide a liquid container capable of reliably detecting a liquidconsumption status in the liquid container even if the piezoelectricdevice is mounted on the upper side of the liquid surface in the liquidcontainer.

Furthermore, it is still another object of the present invention toprovide a liquid container which does not need to be mounted on theaccurate position, in other words, the mounting position of thepiezoelectric device on the liquid container can be freely designed.

These objects are achieved by combinations described in the independentclaims. The dependent claims define further advantageous and exemplarycombinations of the present invention.

According to an aspect of the present invention, there is provided aliquid container which may comprise: a housing containing thereinliquid; a liquid supply opening formed in the housing for withdrawingthe liquid from the housing; a liquid sensor mounted on the housing fordetecting a level of the liquid which is variable in accordance with aconsumption of the liquid; and a first partition wall extending in aninterior of the housing and defining the interior of the housing into atleast two liquid accommodating chambers which communicate with eachother, the liquid accommodating chambers comprising: anair-communication side liquid accommodating chamber which communicateswith ambient air; and a detection side liquid accommodating chamber inwhich the liquid sensor is disposed at an upper portion thereof.

The liquid container may further comprises a porous member accommodatedwithin the detection side liquid accommodating chamber. The liquidsupply opening may be formed in the air-communication side liquidaccommodating chamber. The liquid supply opening may be formed in thedetection side liquid accommodating chamber. A volume of theair-communication side liquid accommodating chamber may be differentfrom that of the detection side liquid accommodating chamber. Thevolumes of the at least two liquid accommodating chambers may decreasefrom one side wall of the housing to the other opposite wall.

The liquid container may further comprising a second partition wallextending in the detection side liquid accommodating chamber anddefining at least two small detection chambers. The second partitionwall may be formed with a liquid communication opening at a lower partthereof. The second partition wall may be formed with a liquidcommunication opening at an upper part thereof. The detection sensor maybe disposed on each of the small detection chambers. The volumes of thesmall detection chambers may be different from each other. The volumesof the at least two small detection chambers may decrease from one sidewall of the housing to the other opposite wall.

The detection side liquid accommodating chamber may generate nocapillary force for holding the liquid. The small detection chamber maygenerate no capillary force for holding the liquid. The detection sideliquid accommodating chamber may comprise a recessed part formed at atop wall thereof. The liquid sensor may comprise a cavity which openstoward an interior of the housing for holding the liquid. The liquidsensor may comprise a piezoelectric device having a vibrating section,the vibrating section generates a counter electromotive force inaccordance with a residual vibration of the vibrating section.

The liquid sensor may detect at least an acoustic impedance of theliquid and detects a liquid consumption status in accordance with theacoustic impedance. The liquid container may be mounted on an ink-jetprinting apparatus having a printhead which ejects ink droplets, and theliquid container supplies the liquid contained therein to the printheadthrough the liquid supply opening. The volume of the detection sideliquid accommodating chamber may be equal to or less than half thevolume of the air-communication side liquid accommodating chamber. Thevolumes of the liquid accommodating chambers may decrease from one sidewall of the housing to the other opposite wall.

The porous member may comprise a first porous material disposed close tothe liquid sensor and a second porous material disposed far from theliquid sensor compared with the first porous material, and the secondporous material has a higher liquid-philic characteristics than thefirst porous material. The liquid sensor may comprise a piezoelectricdevice having a vibrating section, the vibrating section generates acounter electromotive force in accordance with a residual vibration ofthe vibrating section. The liquid sensor may detect at least an acousticimpedance of the liquid and detects a liquid consumption status inaccordance with the acoustic impedance. The liquid container may bemounted on an ink-jet printing apparatus having a printhead which-ejectsink droplets, and the liquid container supplies the liquid containedtherein to the printhead through the liquid supply opening.

According to another aspect of the present invention, there is provideda liquid container which may comprise: a housing containing thereinliquid; a liquid supply opening supplying liquid to an exterior of thehousing; a detection device mounted on the housing, the detection devicecomprising a piezoelectric element for detecting a liquid consumptionstatus; and a wave absorbing wall extending in an interior of thehousing disposed at a place facing the detection device. A gap may bedefined between the detection device and the wave absorbing wall. Thegap may not generate a capillary force for holding the liquid.

The gap may generate a capillary force which is smaller than a force forholding the liquid. The detection device may comprise a cavity forreceiving and holding liquid, the cavity being formed to open toward theinterior of the housing. The wave absorbing wall may be secured to andextends from an interior wall of the housing. The detection device maybe attached to a first wall of the housing which extends in a verticaldirection of the liquid level, and the wave absorbing wall may extend inparallel with the first wall of the housing.

The detection device may be attached to a bottom wall of the housing,and the wave absorbing wall may extend in parallel with the liquidlevel. The wave absorbing wall may extend in an inclined direction withrespect to the liquid level. The wave absorbing wall may extend from aside wall of the housing which is perpendicular to the liquid level. Thea capillary force may be generated between at least a part of theinternal wall and an inner wall of the housing. The wave absorbing wallmay comprise a bending section which is formed by bending at least apart of an edge of the wave absorbing wall toward a wall on which thedetection device is mounted, and a gap defined by the bending sectionand the detection device generates a capillary force while a gap definedby the wave absorbing wall and the detection device does not generate acapillary force.

The wave absorbing wall may comprise a plurality of wave absorbing wallpieces, and at least one of the plurality of wave absorbing wall piecesmay extend from a side wall of the housing which is perpendicular to theliquid level. The detection device may comprise a vibrating sectionwhich generates a counter electromotive force in accordance with aresidual vibration of the vibrating section. The liquid container may bemounted on an ink-jet printing apparatus having a printhead which ejectsink droplets, and the liquid container may supply the liquid containedtherein to the printhead through the liquid supply opening.

According to the other aspect of the present invention, there isprovided a liquid container may comprise: a housing containing thereinliquid; a liquid supply opening formed in a wall of the housing forwithdrawing the liquid to an exterior; a detection device mounted on thehousing, the detection device comprising a piezoelectric element fordetecting a liquid consumption status; and a porous member disposedwithin the housing in the vicinity of the detection device. Thedetection device may contact the porous member. A gap may be definedbetween the porous member and the detection device.

The detection device may comprise a cavity and a vibrating section whichcontacts the liquid through the cavity, and the porous member isdisposed in the cavity. A capillary force of the porous member may besmaller than a force which holds the liquid. The detection device maycomprise a base plate, a vibrating portion and a through hole formed inthe base plate, and the porous member covers at least a part of thethrough hole. The detection device may further comprise a grooveconnecting with the through hole, and the porous member is disposed onthe groove. The detection device and the porous member may be disposedon a plane where the liquid supply opening is formed.

The detection device may comprise a vibrating section which generates acounter electromotive force in accordance with a residual vibration ofthe vibrating section, and the detection device detects the liquidconsumption status in accordance with the counter electromotive force.The detection device may comprise a piezoelectric element and a mountingstructure unitarily formed with the piezoelectric element, and themounting structure is attached to the housing. The liquid container maybe mounted on an ink-jet printing apparatus having a printhead whichejects ink droplets, and the liquid container supplies the liquidcontained therein to the printhead through the liquid supply opening.

This summary of the invention does not necessarily describe allnecessary features of the present invention. The present invention mayalso be a sub-combination of the above described features. The above andother features and advantages of the present invention will become moreapparent from the following description of embodiments taken inconjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1(A) and 1(B) show a side cross sectional view of an embodiment ofthe ink cartridge according to the present invention.

FIG. 2 shows a side cross sectional view of the other embodiment of theink cartridge according to the present invention.

FIGS. 3(A) and 3(B) show a side cross sectional view of the furtherother embodiment of the ink cartridge according to the presentinvention.

FIG. 4 shows a side cross section of the further other embodiment of theink cartridge according to the present invention.

FIGS. 5(A) and 5(B) show a side cross section of the further otherembodiment of the ink cartridge according to the present invention.

FIGS. 6(A) and 6(B) show a side cross section of the further otherembodiment of the ink cartridge according to the present invention.

FIGS. 7(A) and 7(B) show a side cross section of the further otherembodiment of the ink cartridge according to the present invention.

FIG. 8 shows a side cross section of the further other embodiment of theink cartridge according to the present invention.

FIG. 9 shows a side cross section of the further other embodiment of theink cartridge according to the present invention.

FIG. 10 shows a side cross section of the further other embodiment ofthe ink cartridge according to the present invention.

FIG. 11 shows a side cross section of the further other embodiment ofthe ink cartridge according to the present invention.

FIG. 12 shows a side cross section of the further other embodiment ofthe ink cartridge according to the present invention.

FIG. 13 shows a side cross section of the further other embodiment ofthe ink cartridge according to the present invention.

FIG. 14 is a perspective view of the ink cartridge which stores pluraltypes of inks, viewed from a back side thereof, according to anembodiment.

FIG. 15 is a perspective view of the ink cartridge which stores pluraltypes of inks, viewed from a back side thereof, according to anembodiment.

FIG. 16 is a perspective view of the ink cartridge which stores pluraltypes of inks, viewed from a back side thereof, according to anembodiment.

FIG. 17 is a perspective view of the ink cartridge which stores pluraltypes of inks, viewed from a back side thereof, according to anembodiment.

FIG. 18 is a cross sectional view showing an embodiment of a major partof the ink-jet recording apparatus suitable for the ink cartridge shownin FIG. 1.

FIG. 19 is a detailed cross sectional view of a subtank unit 33 as anembodiment of the liquid container according to the present invention.

FIG. 20 is a cross sectional view of another embodiment of a subtankunit 33 of the liquid container according to the present invention.

FIG. 21 is a cross sectional view of further another embodiment of asubtank unit 33 of the liquid container according to the presentinvention.

FIGS. 22(A) to 22(C) show a detail and equivalent circuit of an actuator106, which is an embodiment of the piezoelectric device of the presentinvention.

FIGS. 23(A) to 23(F) show a detail and equivalent circuit of an actuator106, which is an embodiment of the piezoelectric device of the presentinvention.

FIGS. 24(A) and 24(B) are graphs which show the relationship between theink quantity inside the ink tank and the resonant frequency fs of theink and the vibrating section.

FIGS. 25(A) and 25(B) show a waveform of the residual vibration of theactuator 106 and the measuring method of the residual vibration.

FIG. 26 shows the manufacturing method of the actuator 106. A pluralityof the actuators 106, four numbers in the case of the FIG. 26, areformed as one body.

FIG. 27 shows a cross-section of a part of the actuator 106.

FIG. 28 shows a cross-section of the actuator 106.

FIG. 29 shows the manufacturing method of the actuator 106 shown in FIG.26.

FIG. 30 shows the further other embodiment of the ink cartridge of thepresent invention.

FIGS. 31(A) to 31(C) show further other embodiment of the ink cartridgeof the present invention.

FIGS. 32(A) to 32(C) show other embodiment of the through hole 1 c.

FIGS. 33(A) and 33(B) are slant views of the further other embodiment ofthe actuator.

FIG. 34 shows a slant view of the other embodiment of the actuator.

FIGS. 35(A) to 35(C) show plan views of the through hole 1 c accordingto another embodiment.

FIG. 36 shows a slant view of the configuration that forms the actuator106 in one body as a mounting module 100.

FIG. 37 shows an exploded view of the module 100 shown in FIG. 36 toshow the structure of the module 100.

FIG. 38 shows the slant view of the other embodiments of the module.

FIG. 39 shows an exploded view of the module 400 shown in FIG. 38 toshow the structure of the module 400.

FIG. 40 shows the further other embodiment of the module.

FIG. 41 shows a cross-sectional view around the bottom of the container1 when the module 100 shown in FIG. 36 is mounted on the container 1.

FIGS. 42(A) to 42(C) show the cross section of the ink container whenmounting module 700B on the container 1.

FIG. 43 shows an embodiment of an ink cartridge and an ink jet recordingapparatus which uses the actuator 106 shown in FIG. 22.

FIG. 44 shows a detail around the head member of the ink jet recordingapparatus.

FIGS. 45(A) and 45(B) show other embodiment of the ink cartridge 180shown in FIG. 44.

FIGS. 46(A) to 46(C) show further other embodiment of the ink cartridge180.

FIGS. 47(A) and 47(B) show further other embodiment of the ink cartridge180.

FIGS. 48(A) to 48(D) show further other embodiment of the ink cartridge180.

FIG. 49 shows a plan cross sectional view of the further anotherembodiment of the ink cartridge according to the present invention.

FIG. 50 shows a plan cross sectional view of the further anotherembodiment of the ink cartridge according to the present invention.

FIGS. 51(A) to 51(D) show other embodiment of the ink cartridge usingthe actuator 106.

FIG. 52 is a cross sectional view of an embodiment of an ink cartridgeas an embodiment of the liquid container according to the presentinvention.

FIG. 53 is a perspective view of the ink cartridge which stores pluraltypes of inks, viewed from an outside thereof, according to anembodiment.

FIG. 54 is a cross sectional view showing an embodiment of a major partof the ink-jet recording apparatus suitable for the ink cartridge shownin FIG. 52 and FIG. 53.

FIG. 55 is a cross sectional view of an another embodiment of an inkcartridge as an embodiment of the liquid container according to thepresent invention.

FIG. 56 shows further other embodiment of the ink cartridge using theactuator 106.

FIG. 57 shows further another embodiment of the ink cartridge using theactuator 106.

FIG. 58 shows further another embodiment of the ink cartridge 180.

FIG. 59 shows further another embodiment of the ink cartridge 180.

FIG. 60 shows further another embodiment of the ink cartridge 180.

FIG. 61 shows further another embodiment of the ink cartridge 180.

FIG. 62 shows further another embodiment of the ink cartridge 180.

FIG. 63 shows further another embodiment of the ink cartridge 180.

FIG. 64 shows further other embodiment of the ink cartridge 180.

FIG. 65 shows further other embodiment of the ink cartridge 180.

FIG. 66 shows further other embodiment of the ink cartridge 180.

FIG. 67 shows an embodiment around a recording head of part of the inkcartridge and an ink jet recording apparatus which uses the actuator106.

FIG. 68 shows a detail around the head member of the ink jet recordingapparatus.

FIG. 69 is a cross sectional view of an embodiment of an ink cartridgeas an embodiment of the liquid container according to the presentinvention.

FIG. 70 is a cross sectional view of an embodiment of an ink jetrecording apparatus and ink cartridge according to the presentinvention.

FIG. 71 is a cross sectional view of a further another embodiment of anink cartridge as an embodiment of the liquid container according to thepresent invention.

FIG. 72 shows further another embodiment of the ink cartridge using theactuator 106.

FIG. 73 shows further another embodiment of the ink cartridge using theactuator 106.

FIG. 74 shows further another embodiment of the ink cartridge using theactuator 106.

FIG. 75 shows a cross section of an ink cartridge 180D which is furtherother embodiment of the ink cartridge 180 using actuator 106.

FIGS. 76(A) and 76(B) show further another embodiment of the inkcartridge using actuator 106.

FIG. 77 shows further another embodiment of the ink cartridge usingactuator 106.

FIG. 78 shows further another embodiment of the ink cartridge using theactuator 106.

FIG. 79 shows further another embodiment of the ink cartridge 180.

FIG. 80 shows further another embodiment of the ink cartridge 180.

FIG. 81 shows further another embodiment of the ink cartridge 180.

FIG. 82 shows further another embodiment of the ink cartridge 180.

FIG. 83 shows further another embodiment of the ink cartridge 180.

FIG. 84 shows further another embodiment of the ink cartridge 180.

FIG. 85 shows further other embodiment of the ink cartridge using theactuator 106.

FIG. 86 shows further other embodiment of the ink cartridge 180.

FIG. 87 shows further other embodiment of the ink cartridge 180.

FIG. 88 shows an embodiment around a recording head of part of the inkcartridge and an ink jet recording apparatus which uses the actuator106.

FIG. 87 shows further other embodiment of the ink cartridge 180.

FIG. 88 shows an embodiment around a recording head of part of the inkcartridge and an ink jet recording apparatus which uses the actuator106.

FIG. 89 shows a detail around the head member of the ink jet recordingapparatus.

FIG. 90 is a cross sectional view of an embodiment of an ink cartridgefor use with a single color, for example, the black ink.

FIG. 91 is a cross sectional view showing an embodiment of a major partof the ink-jet recording apparatus suitable for the ink cartridge shownin FIG. 90.

FIG. 92 is a detailed cross sectional view of a subtank unit 33.

FIGS. 93(A) and 93(B) are cross sectional views showing anotherembodiment of the ink cartridge.

FIGS. 94(I) to (V) show manufacturing methods of the elastic wavegenerating device 3, 15, 16 and 17.

FIG. 95 shows manufacturing methods of the elastic wave generatingdevice 3, 15, 16 and 17.

FIG. 96 shows an ink cartridge according to another embodiment of thepresent invention.

FIG. 97 shows ink cartridges according to still another embodiments ofthe present invention.

FIG. 98 shows ink cartridges according to still another embodiments ofthe present invention.

FIG. 99 shows an ink cartridge according to still another embodiment ofthe present invention.

FIG. 100 shows a cross section of the ink-jet recording apparatus alone.

FIG. 101 is a cross section of the ink-jet recording apparatus to whichthe ink cartridge 272 is mounted.

FIG. 102 shows an embodiment of the ink cartridge for use with a singlecolor, for instance, the black color.

FIG. 103 shows an ink cartridge 272 according to still anotherembodiment of the present invention.

FIG. 104 shows an ink cartridge 272 and an ink-jet recording apparatusaccording to still another embodiment of the present invention.

FIG. 105 is a cross sectional view of an embodiment of an ink cartridgefor use with a single color, for example, the black ink.

FIGS. 106(A) and 106(B) are cross sectional views of the bottom part ofthe ink cartridge of the present embodiment.

FIG. 107 is a cross sectional view showing an embodiment of a major partof the ink-jet recording apparatus suitable for the ink cartridge shownin FIG. 105 and FIG. 106.

FIG. 108 is a cross sectional view of another embodiment of a subtankunit 33.

FIG. 109 show ink cartridges according to still another embodiments ofthe present invention.

FIG. 110 shows an ink cartridge according to still another embodiment ofthe present invention.

FIGS. 111(A) to 111(C) show other embodiment of the through hole 1 c.

FIG. 112 is a slant view of the further other embodiment of theactuator.

FIG. 113 shows a further embodiment of the ink cartridge 180.

FIG. 114 shows further other embodiment of the ink cartridge 180.

FIGS. 115(A) to 115(C) show further other embodiment of the inkcartridge 180.

DETAILED DESCRIPTION OF THE INVENTION

The invention will now be described based on the preferred embodiments,which do not intend to limit the scope of the present invention, butexemplify the invention. All of the features and the combinationsthereof described in the embodiment are not necessarily essential to theinvention.

The basic concept of the present invention is to detect a state of theliquid inside a liquid container by utilizing vibration phenomena. Thestate of the liquid includes whether or not the liquid in the liquidcontainer is empty, amount of the liquid, level of the liquid, types ofthe liquid and combination of liquids. Several specific methodsrealizing for detection of the state of the liquid inside the liquidcontainer utilizing vibration phenomena are considered. For example, amethod is considered in which the medium and the change of its stateinside the liquid container are detected in such a manner that anelastic wave generating device generates an elastic wave inside theliquid container, and then the reflected wave which is thus reflected bythe liquid surface or a wall disposed counter thereto is captured. Thereis another method in which a change of acoustic impedance is detected byvibrating characteristics of a vibrating object.

As a method utilizing the change of the acoustic impedance, a vibratingportion of a piezoelectric device or an actuator having a piezoelectricelement therein is vibrated. Thereafter, a resonant frequency or anamplitude of the back electromotive force waveform is detected bymeasuring the back electromotive force which is caused by residualvibration which remains in the vibrating portion, so as to detect thechange of the acoustic impedance. As another method utilizing the changeof the acoustic impedance, the impedance characteristic or admittancecharacteristic of the liquid is measured by a measuring apparatus suchas an impedance analyzer and a transmission circuit, so that the changeof a current value or a voltage value, or the change of the currentvalue or voltage value due to the frequency caused by the vibrationgiven to the liquid is measured.

In the present embodiment, the medium in the liquid container and thechange of the status of the medium in the liquid container is detectedusing the piezoelectric device or actuator to detect the residualvibration remained in the vibrating section of the piezoelectric deviceand the actuator.

FIG. 1 to FIG. 13 is a cross sectional view of an embodiment of an inkcartridge for use with a single color, for example, the black ink as anembodiment of the liquid container according to the present invention.An ink cartridge according to the present embodiment comprises acontainer 1 which contains liquid K, a ink supply port 2 which suppliesliquid K outside the container 1, an actuator 106 which detects inkconsumption status inside the container 1, and a wave preventing wallwhich provided at the position that faced to the actuator 106.

A packing ring 4 and a valve body 6 are provided in the ink supply port2. Referring to FIG. 18, the packing ring 4 is engaged with the inksupply needle 32 communicating with a recording head 31, in afluid-tight manner. The valve body 6 is constantly and elasticallycontacted against the packing ring 4 by way of a spring 5. When the inksupply needle 32 is inserted, the valve body 6 is pressed by the inksupply needle 32 so as to open an ink passage, so that ink inside thecontainer 1 is supplied to the recording head 31 via the ink supply port2 and the ink supply needle 32. On an upper wall of the container 1,there is mounted a semiconductor memory means 7 which stores data on inkinside the ink cartridge.

FIG. 1(A) shows a side cross sectional view of an embodiment of the inkcartridge according to the present invention. In FIG. 1 to FIG. 4, thewave preventing wall 1192 a to 1192 d is extended horizontally to theink surface. Furthermore, the actuator 106 is mounted on the bottom face1 a which is located lower side of the ink surface. As shown in FIG.1(A), the ink supply port 2 that engages with the ink supply needle ofthe recording apparatus is provided on the container 1 which containsink. The actuator 106 is mounted on the outside the bottom face 1 a ofthe container 1 so that the actuator 106 can contacts with ink insidethe container 1 through the through hole 1 c which is provided on hecontainer 1. The actuator 106 is provided on the position which ishigher than the ink supply port 2 so that when ink K is almost used up,that is, at the time of the ink near end, the propagation of the elasticwave can change from ink to gas. The actuator 106 can be used as onlyfor the means of merely detecting the vibration generated in the inkcartridge without generating a vibration by itself.

FIG. 1(B) shows a cross sectional view from the front of an embodimentof the ink cartridge according to the present embodiment. As shown inFIG. 1(B), the container 1 has a side wall 1020 which extendssubstantially vertical direction to the liquid surface. The wavepreventing wall 1192 a is fixed to the container 1 by mounting on theside wall 1020 of the container 1.

A gap is provided between the actuator 106 and the wave preventing wall1192 a. If ink is filled in the ink cartridge, ink is filled in the gapbetween the actuator 106 and the wave preventing wall 1192 a. On theother hand, the gap is designed such that ink is not held in the gapbetween the actuator 106 and the wave preventing wall 1192 a if ink inthe ink cartridge is used up. In other words, no capillary force forholding ink arises between the actuator 106 and the wave preventing wall1192 a.

Because the through hole 1 c is provided on the container 1, ink remainsin the through hole 1 c even the ink inside the container 1 is consumed.Therefore, even when the ink cartridge vibrates by such as scanningoperation during the printing process and thus ink nearby the ink supplyport 2 rolls, ink does not mistakenly attach to the actuator 106 becauseink previously remains in the through hole 1 c. Thus, there is onlylittle possibility for the actuator 106 to mistakenly detect theexistence of ink.

The wave preventing wall is provided to face to the actuator 106 in theink cartridge according to the present embodiment. Therefore, even inknearby the ink supply port 2 rolls, the wave preventing wall preventsthe rolled ink to be contact with the actuator 106. Therefore, Thus,there is only little possibility for the actuator 106 to mistakenlydetect the existence of ink.

Furthermore, bubbles may be generated by the waving of ink, which iscaused by the vibration of ink cartridge generated by such as thescanning operation during the printing process. Then, there is dangerthat the actuator 106 may detect mistakenly that there is no ink if thebubble attaches to the actuator 106 even if the ink is filled in thecontainer 1. However, according to the configuration of the presentembodiment, the wave preventing wall prevents the waving of ink aroundthe piezoelectric device even when the ink cartridge vibrates by such asthe scanning operation during the printing process. By preventing thewaving of ink around the piezoelectric device, the wave preventing wallprevents the generation of the bubbles. Furthermore, even the bubblesgenerate, the wave preventing wall prevents the bubbles to move close tothe actuator 106 and contact with the actuator 106 because the wavepreventing wall is provided such that the wave preventing wall faces tothe actuator 106.

There is no limitation of the size, shape, flexibility, and material forthe wave preventing wall. Therefore, the size of the wave preventingwall can be made further larger or can be made further smaller. Thethickness of the wave preventing wall can be made further thicker or canbe made further thinner. Furthermore, the shape of the wave preventingwall can be square, rectangular, polygon, or an ellipse. Furthermore,the wave preventing wall can be made from the hard material or flexiblematerial. Furthermore, the wave preventing wall can be made from theair-tight or liquid-tight material. Conversely, the wave preventing wallcan be made from the breathability material or material which can pasthrough liquid. As an example of the air-tight or liquid-tight material,there are plastic, tefron, nylon, polypropylene, or PET. On the otherhand, as an example of the breath ability material or a material whichpass through liquid, there are porous material constituted by such asnylon or a material having a mesh structure. Furthermore, the porousmaterial used for the wave preventing wall can be negative pressuregenerating member.

Preferably, the container 1 and the wave preventing wall is formed by asame material such that both of the container 1 and the wave preventingwall can be formed as one body. Then, the manufacturing process of theink cartridge can be reduced.

Because ink cannot be supplied from the ink supply port 2 to therecording head if the pressure inside the ink cartridge becomesextremely negative with the ink consumption, airhole, not shown infigure, is provided on a part of the container so that the pressureinside the ink cartridge does not become extreme negative.

FIG. 2 shows a side cross sectional view of the other embodiment of theink cartridge according to the present invention. As shown in FIG. 2, awave preventing wall 1192 b is mounted on the side wall 1030 whichextends to the vertical direction to the ink surface. The cross sectionviewed from the front of the ink cartridge according to the presentembodiment is same as the cross section shown in one of FIG. 1(B) orFIG. 3(B).

The wave preventing wall 1192 b of the ink cartridge of the presentembodiment extends longer than the wave preventing wall 1192 a of theembodiment shown in FIG. 1. Therefore, the wave preventing wall 1192 bcan effectively protects the actuator 106 from the wave of ink.

FIG. 3(A) shows a side cross sectional view of the further otherembodiment of the ink cartridge according to the present invention. Asshown in FIG. 3(A), a side wall 1010 and a side wall 1030, which extendto the vertical direction to the ink surface, faces each other. The wavepreventing wall 1192 c extends from the side wall 1010 to the side wall1030.

FIG. 3(B) shows a cross sectional view from the front of the inkcartridge of FIG. 3(A). A gap is provided between the side wall 1020 andthe wave preventing wall 1192 c so that ink can pass through the gap.

FIG. 4 shows a side cross section of the further other embodiment of theink cartridge according to the present invention. In the presentembodiment, the actuator 106 is provided on the sloped face formed onthe bottom face 1 a. The wave preventing wall 1192 d extends from theperiphery of the ink supply port 2 within the inside wall of thecontainer to face to the actuator 106.

FIG. 5(A) shows a side cross section of the further other embodiment ofthe ink cartridge according to the present invention.

In FIG. 5 to FIG. 7, the actuator 106 is mounted on the side wall 1030which extends to the vertical direction to the ink surface. Furthermore,the wave preventing wall 1192 e to 1192 g extends substantially verticalto the ink surface, that is, parallel with the side wall 1030.

The wave preventing wall 1192 e is provided on the position wheredirectly faces to the actuator 106. The wave preventing wall 1192 eextends from the bottom face 1 a. Furthermore, a gap is provided betweenthe top wall 1040 and the top of wave preventing wall 1192 e.

FIG. 5(B) shows a cross sectional view from the front of the inkcartridge of FIG. 5(A). A gap is provided between the side wall 1020 andthe wave preventing wall 1192 e so that ink can pass through the gap.Because of the gap, ink does not remain in the actuator 106 side of thecontainer 1, which is formed by partitioning the container 1 by the wavepreventing wall 1192 e, even if ink is consumed. Therefore, the level ofink surface around the actuator 106 is always equal to the level of theink surface of the other region of the container 1. Thus, the actuator106 does not detect mistakenly the ink consumption status.

Furthermore, the length of the wave preventing wall 1192 e from thebottom face 1 a can be changed according to the height of the actuator106 to the level of the ink surface and the probability of thegeneration of ink wave which is influenced by the viscosity of ink.Furthermore, interval of the gap between the wave preventing wall 1192 eand the side wall 1020 can be changed according to the position of theactuator 106 on the width direction of the ink cartridge, the magnitudeof the vibrating region of the actuator 106, or the characteristic ofink.

FIG. 6(A) shows a side cross section of the further other embodiment ofthe ink cartridge according to the present invention. the actuator 106is mounted on the side wall 1030. A wave preventing wall 1192 f ismounted on the position where directly faces to the actuator 106. Thewave preventing wall 1192 f extends from the top wall 1040. Furthermore,a gap is provided between the bottom face 1 a and the wave preventingwall 1192 f.

FIG. 6(B) shows a cross sectional view from the front of the inkcartridge of FIG. 6(A). The wave preventing wall 1192 f is coupled tothe side wall 1020 liquid tightly so that ink can not pass throughbetween the wave preventing wall 1192 f and the side wall 1020. By thisconfiguration, ink remains only in the side of the actuator 106 which isformed by partitioning the container 1 by the wave preventing wall 1192f, even if ink is consumed. However, when ink surface reaches to thelower end of the wave preventing wall 1192 f, gas enters to the actuator106 side of the container 1 partitioned by the wave preventing wall 1192f. By the entering of the gas, ink remained in the actuator 106 side ofthe container 1 partitioned by the wave preventing wall 1192 f flows outto the ink supply port 2 side, then the medium exits around the actuator106 changes from ink to gas. Thereby the actuator 106 can detect thatthe ink inside the ink cartridge is in status of ink end. According tothe present embodiment, lower end 192 a determines the level of inksurface to be an ink end. Therefore, as far as the actuator 106 isprovided on the position upper than the lower end 192 a to the inksurface, actuator 106 can be located in any position on the wall face1030. An airhole, which introduces gas, is provided on the top wall ofthe ink supply port 2 side of the container 1 partitioned by the wavepreventing wall 1192 f.

FIG. 7(A) shows a side cross section of the further other embodiment ofthe ink cartridge according to the present invention. The actuator 106is mounted on the side wall 1030 which is vertical to the ink surfaceamong the wall of the container 1. A wave preventing wall 1192 g isprovided on the position where directly faces to the actuator 106. Thewave preventing wall 1192 g extends from the bottom face 1 a to the topwall 1040.

FIG. 7(B) shows a cross sectional view from the front of the inkcartridge of FIG. 7(A). A gap is provided between the wave preventingwall 1192 g and the side wall 1020 so that ink can pass through the gap.By this configuration, ink does not remain in the side of the actuator106 which is formed by partitioning the container 1 by the wavepreventing wall 1192 g, even if ink is consumed. Therefore, the level ofink surface around the actuator 106 is always equal to the level of inksurface of the other region of container 1. Furthermore, the interval ofthe gap between the wave preventing wall 1192 g and the side wall 1020can be changed according to the position of the actuator 106 on thewidth direction of the ink cartridge, or the characteristic of ink.

FIG. 8 to FIG. 11 show a side cross section of the further otherembodiment of the ink cartridge according to the present invention. Theactuator 106 is mounted on the side wall 1010 where the ink supply port2 is provided.

In FIG. 8, the wave preventing wall 1192 i is provided on the positionwhere directly faces to the actuator 106. The wave preventing wall 1192i extends from the supply port wall 2 a which is a outside wall of theink supply port 2 among the inside wall nearby the ink supply port 2 ofthe ink cartridge. On the other hand, a gap is provided between the topwall 1040 and the wave preventing wall 1192 i.

Because the cross section viewed from the front of the ink cartridge ofthe present invention is similar to FIG. 5(B), the figure of which willbe omitted for FIG. 8. There is a gap between the wave preventing wall1192 i and the side wall 1020. Because of the gap, ink does not remainin the actuator 106 side of the container 1, which is formed bypartitioning the container 1 by the wave preventing wall, even if ink isconsumed 1192 i as the embodiment shown in FIG. 5. Therefore, the levelof ink surface around the actuator 106 is always equal to the level ofthe ink surface of the other region of the container 1.

In FIG. 9, the wave preventing wall 1192 j is provided on the positionwhere directly faces to the actuator 106. The wave preventing wall 1192j extends from the top wall 1040. On the other hand, a gap is providedbetween the supply port wall 2 a and the wave preventing wall 1192 j.

Because the cross section viewed from the front of the ink cartridge ofthe present invention is similar to FIG. 6(B), the figure of which willbe omitted for FIG. 9. The wave preventing wall 1192 j is coupled to theside wall 1020 liquid so that ink can not pass through between the wavepreventing wall 1192 j and the side wall 1020. Therefore, as theembodiment shown in FIG. 6, as far as the actuator 106 is provided onthe position upper than the lower end 192 a to the ink surface, theactuator 106 can be located in any position on the wall face 1030.

In FIG. 10, the wave preventing wall 1192 k is provided on the positionwhere directly faces to the actuator 106. The wave preventing wall 1192k extends from the top wall 1040 to the supply port wall 2 a.

Because the cross section viewed from the front of the ink cartridge ofthe present invention is similar to FIG. 7(B), the figure of which willbe omitted for FIG. 10. A gap is provided between the wave preventingwall 1192 k and the side wall 1020 as shown in FIG. 7(B). Therefore, inkdoes not remain in the side of the actuator 106 which is formed bypartitioning the container 1 by the wave preventing wall 1192 k, even ifink is consumed as same as the embodiment of FIG. 5. Therefore, thelevel of ink surface around the actuator 106 is always equal to thelevel of ink surface of the other region of container 1.

FIG. 11 to FIG. 13 show a side cross section of the further otherembodiment of the ink cartridge according to the present invention. Theactuator 106 is mounted on the boundary between the bottom face 1 a,which is located below the ink surface, and the side wall 1030, whichextends vertical to the ink surface.

In FIG. 11, a wave preventing wall 1192 m is fixed to the container 1such that one end of a wave preventing wall 1192 m is connected to thebottom face 1 a, and the other end of which is connected to the sidewall 1030. The wave preventing wall 1192 m is provided on the container1 such that the wave preventing wall 1192 m directly faces to theactuator 106 and slopes to the ink surface. There is a gap between theside wall 1020 and the wave preventing wall 1192 m among the wall of thecontainer 1 in the present embodiment. Therefore, the level of inksurface around the actuator 106 is always equal to the level of inksurface of the other region of container 1 even if ink is consumed.Furthermore, the shape of the wave preventing wall 1192 m of the presentembodiment is substantially plane shape.

Because the ink cartridge according the present embodiment mounting theactuator 106 on the boundary of the wall of the container 1, thepositioning of the actuator 106 on the container 1 during themanufacturing of the ink cartridge becomes easy. Moreover, because thelength or the width of the wave preventing wall 1192 m can be shorten,the quantity of the material used for manufacturing the wave preventingwall 1192 m is reduced. Furthermore, even in the case of manufacturingthe wave preventing wall 1192 m as a independent material with thecontainer 1, it is relatively easy to positioning the wave preventingwall 1192 m on the boundary of the wall of the container 1. Therefore,the manufacturing of the ink cartridge 180 becomes easy.

In FIG. 12, the position of mounting the actuator 106 and the wavepreventing wall 1192 n on the container 1 is same as the embodiment ofthe FIG. 11. On the other hand, the shape of the wave preventing wall1192 n is a part of the spherical shell in the present embodiment. Byshaping the wave preventing wall 1192 n in a shape of spherical shell,the distance between the actuator 106 and the all the part of the wavepreventing wall 1192 n becomes equal. Thereby the wave preventing wall1192 n does not influence the residual vibration detected by theactuator 106.

Furthermore, the wave preventing wall 1192 n can be formed as a part ofthe hollow cylindrical shape.

In FIG. 13, the position of mounting the actuator 106 and the wavepreventing wall 1192 p on the container 1 is same as the embodiment ofthe FIG. 11. On the other hand, the wave preventing wall 1192 p isformed in an L-shape in the present embodiment. The wave preventing wall1192 p is provided on the container 1 such that the wave preventing wall1192 p has a same distance with the side wall 1030 and the bottom face 1a. By shaping the wave preventing wall 1192 n in a L-shape and reducingthe gap between the wave preventing wall 1192 p and the actuator 106 aslong as the capillary force does not arise between the wave preventingwall 1192 p and the actuator 106, the waving and bubbling of ink aroundthe actuator 106 can be effectively prevented.

FIG. 14 is a perspective view of the ink cartridge which stores pluraltypes of inks, viewed from a back side thereof, according to anembodiment. A container 8 is divided by division walls into three inkchambers 9, 10 and 11. Ink supply ports 12, 13 and 14 are formed for therespective ink chambers. In a bottom face 8 a of the respective inkchambers 9, 10 and 11, the respective actuator 15, 16 and 17 are mountedon the container 8 so that the actuator can contact with the ink whichis housed in each ink chamber via the through hole provided on thecontainer 8.

Each of three different wave preventing walls, not shown in the figure,is provided on the position of each of inside of the ink container 9, 10and 11 such that the each of the wave preventing walls faces to the eachof actuators 15, 16, and 17.

FIG. 15 is a perspective view of the ink cartridge which stores pluraltypes of inks, viewed from a back side thereof, according to anembodiment. A container 8 is divided by partition walls into three inkchambers 9, 10 and 11. Ink supply ports 12, 13 and 14 are formed for therespective ink chambers. In a side wall 1028 which extends vertically tothe ink surface of the respective ink chambers 9, 10 and 11, therespective actuators 15, 16 and 17 are mounted on the container 8. Eachof the actuators 15, 16, and 17 is mounted on the each of the inkchambers 9, 10, 11 so that the each of the actuators 15, 16, and 17 cancontact with the ink which is housed in each ink chamber via the throughhole, not shown in the figure, provided on the container 8. The actuator16 is mounted a tone of the partition wall, which is provided betweenthe ink chamber 9 and the ink chamber 10, and the partition wall, whichis provided between the ink chamber 10 and the ink chamber 11.

Each of the wave preventing walls, not shown in the figure, is providedinside the each of the ink chamber 9, 10, and 11 such that each of thewave preventing walls faces to the actuators 15, 16, and 17 and extendsto the vertical direction to the ink surface.

FIG. 16 is a perspective view of the ink cartridge which stores pluraltypes of inks, viewed from a back side thereof, according to anembodiment. A container 8 is divided by partition walls into three inkchambers 9, 10 and 11. Ink supply ports 12, 13 and 14 are formed for therespective ink chambers. Each of actuators 15, 16 and 17 is mounted onthe container 8 just nearby the each of the ink supply port 12, 13, and14, respectively. Each of the actuators 15, 16, and 17 is mounted on theeach of the ink chambers 9, 10, 11 so that the each of the actuators 15,16, and 17 can contact with the ink which is housed in each ink chambervia the through hole, not shown in the figure, provided on the container8.

Each of the wave preventing walls, not shown in the figure, is providedinside the each of the ink chamber 9, 10, and 11 such that each of thewave preventing walls faces to the actuators 15, 16, and 17 as shown inFIG. 8 to FIG. 11.

FIG. 17 is a perspective view of the ink cartridge which stores pluraltypes of inks, viewed from a back side thereof, according to anembodiment. A container 8 has same constitute element as shown in FIG.14 to FIG. 16. A sloped face which slopes to the ink surface is providedon the bottom face 8 a. Each of actuators 15, 16 and 17 is mounted onthe sloped face 1025 of each of the ink chambers 9, 10, and 11.

Each of the wave preventing walls, not shown in the figure, is providedinside the each of the ink chamber 9, 10, and 11 as shown in FIG. 4.

Furthermore, the actuators 15, 16, and 17 can be provided on theboundary of the walls that adjoin each other in the container 8. In thiscase, each of the wave preventing walls is provided inside the each ofthe ink chambers 9, 10, and 11 as shown in FIG. 11 to FIG. 13.

FIG. 18 is a cross sectional view showing an embodiment of a major partof the ink-jet recording apparatus suitable for the ink cartridge shownin FIG. 1. A carriage 30 capable of reciprocating in the direction ofthe width of the recording paper is equipped with a subtank unit 33,while the recording head 31 is provided in a lower face of the subtankunit 33. Moreover, the ink supply needle 32 is provided in an inkcartridge mounting face side of the subtank unit 33. In the presentembodiment, the ink cartridge shown in FIG. 1 is used. Therefore, thewave preventing wall 1192 a is mounted on the position which faces tothe actuator 106. However, the ink cartridge shown in FIG. 2 to FIG. 17can be used instead of the ink cartridge shown in FIG. 1. Therefore, thewave preventing wall shown in FIG. 2 top FIG. 17 can be used for thepresent embodiment.

FIG. 19 is a detailed cross sectional view of a subtank unit 33 as anembodiment of the liquid container according to the present invention.The subtank unit 33 comprises the ink supply needle 32, the ink chamber34, a flexible valve 36 and a filter 37. In the ink chamber 34, the inkis housed which is supplied from the ink cartridge via ink supply needle32. The flexible valve 36 is so designed that the flexible valve 36 isopened and closed by means of the pressure difference between the inkchamber 34 and the ink supply passage 35. The subtank unit 33 is soconstructed that the ink supply passage 35 is communicated with therecording head 31 so that the ink can be supplied up to the recordinghead 31.

Furthermore, the actuator 106 can be mounted on the side wall 1050 whichextends to vertical direction to the ink surface among the wall of thesubtank unit 33. The actuator 106 is mounted on the side wall 1050 sothat the actuator 106 can contacts with ink inside the ink chamber 34through the through hole 1001 c which is provided on the side wall 1050.The wave preventing wall 1192 q extends from the filter 37 to the upwarddirection to the ink surface so that the wave preventing wall 1192 qfaces to the actuator 106. A gap is provided between the top wall 1060,which locates upward the ink surface, and the wave preventing wall 1192q.

A gap is provided between the actuator 106 and the wave preventing wall1192 q. If ink is filled in the ink cartridge, ink is filled in the gapbetween the actuator 106 and the wave preventing wall 1192 q. On theother hand, if the ink inside the ink cartridge is consumed, ink is notheld in the gap between the actuator 106 and the wave preventing wall1192 q. That is, the capillary force, which holds ink, does not worksbetween the actuator 106 and the wave preventing wall 1192 q.

The cross section of the subtank unit 33 viewed from the direction ofthe side wall 1050 is similar to the cross section of the ink cartridgeshown in FIG. 5(B). A gap is provided between the side wall, not shownin the figure, which adjacent to the side wall 1050 and the wavepreventing wall 1192 q. The level of the ink surface around the actuator106 is always equal to the level of the ink surface of the other regionof the container 1. Therefore, with the consumption of the ink insidethe ink chamber 34, the level of ink surface between the side wall 1050and the wave preventing wall 1192 q also decreases. The actuator 106thereby does not mistakenly detect the ink consumption status.

Furthermore, the length of the wave preventing wall 1192 q from thefilter 37 can be changed according to the position of the actuator 106to the level of the ink surface and the probability of the generation ofink wave which is influenced by the viscosity of ink. Furthermore,interval of the gap between the wave preventing wall 1192 q and the sidewall 1020 can be changed according to the position of the actuator 106on the subtank unit 33, the magnitude of the vibrating region of theactuator 106, or the characteristic of ink.

Referring to FIG. 18, when the ink supply port 2 of the container 1 isinserted through the ink supply needle 32 of the subtank unit 33, thevalve body 6 recedes against the spring 5, so that an ink passage isformed and the ink inside the container 1 flows into the ink chamber 34.At a stage where the ink chamber 34 is filled with ink, a negativepressure is applied to a nozzle opening of the recording head 31 so asto fill the recording head with ink. Thereafter, the recording operationis performed.

When the ink is consumed in the recording head 31 by the recordingoperation, a pressure in the downstream of the flexible valve 36decreases. Then, the flexible valve 36 is positioned away from a valvebody 38 so as to become opened as shown in FIG. 19. When the flexiblevalve 36 is opened, the ink in the ink chamber 34 flows into therecording head 31 through the ink passage 35. Accompanied by the inkwhich has flowed into the recording head 31, the ink in the container 1flows into the subtank unit 33 via the ink supply needle 32.

Moreover, the actuator 106 and the wave preventing wall are provided atleast one of the ink cartridge and the subtank unit. However, theactuator 106 and the wave preventing wall can be provided both of theink cartridge and the subtank unit.

By providing the actuator 106 and the wave preventing wall on both ofthe ink cartridge and the subtank unit, the ink end status of the inkcartridge and the subtank unit can be accurately detected. For example,the recording apparatus can be set to stop the recording operation whenone of the cases arises such that the number of the droplets dischargedfrom the recording head reach to the predetermined number of dropletsduring the measuring of the number of droplets after the actuator 106,which is mounted on the ink cartridge, detects the ink end or that theactuator 106 mounted on the subtank unit 33 detects the ink end.

Furthermore, the recording apparatus can be set to stop the recordingoperation when both of the cases arises such that the number of thedroplets discharged from the recording head reach to the predeterminednumber of droplets after the actuator 106, which is mounted on the inkcartridge, detects the ink end and that the actuator 106 mounted on thesubtank unit 33 detects the ink end.

While the recording apparatus is operating, a drive signal is suppliedto the actuator 106 at a period which is set in advance.

FIG. 20 is a cross sectional view of another embodiment of a subtankunit 33 of the liquid container according to the present invention. Theactuator 106 is mounted on the side wall 1050. The wave preventing wall1192 r extends from the top wall 1060, which is located upside of theink surface, downward to the ink surface. There is a gap between thelower end 192 a of the wave preventing wall 1192 r and the filter 37.Moreover, a gap is provided between the wave preventing wall 1192 r andthe side wall adjacent to the side wall 1050. No capillary force, whichholds ink, arises between the wave preventing wall 1192 r and theactuator 106 as similar to the embodiment shown in FIG. 19.

Because a gap is provided between the wave preventing wall 1192 r andthe side wall adjacent to the side wall 1050, the level of the inksurface around the actuator 106 is always equal to the level of the inksurface of the other region of the container 34. Therefore, the actuator106 detects the ink end status by detecting the ink surface at themounting position of the actuator 106.

FIG. 21 is a cross sectional view of further another embodiment of asubtank unit 33 of the liquid container according to the presentinvention. The actuator 106 is mounted on the side wall 1050. The wavepreventing wall 1192 s extends from the top wall 1060 until the filter37. No capillary force, which holds ink, arises between the wavepreventing wall 1192 s and the actuator 106 as similar to the embodimentshown in FIG. 19.

Furthermore, a gap is provided between the wave preventing wall 1192 sand the side wall adjacent to the side wall 1050. Therefore, the levelof the ink surface around the actuator 106 is always equal to the levelof the ink surface of the other region of the container 34.

FIG. 22 and FIG. 23 shows a detail and equivalent circuit of an actuator106, which is an embodiment of the piezoelectric device of the presentinvention. The actuator explained herein is used at least for the methodwhich detects the liquid consumption status in the liquid container bydetecting a change in acoustic impedance. Especially, the actuator isused for the method which detects the liquid consumption status in theliquid container by detecting at least the change in acoustic impedanceby detecting the resonant frequency from residual vibration. FIG. 22(A)is an enlarged plan view of the actuator 106. FIG. 22(B) shows a B-Bcross-section of the actuator 106. FIG. 22(C) shows a C-C cross-sectionof the actuator 106. FIG. 23(A) and FIG. 23(B) shows an equivalentcircuit of the actuator 106. Each of FIG. 23(C) and FIG. 23(D) shows theactuator 106 and around the actuator 106, and the equivalent circuit ofthe actuator 106 when an ink is filled in the ink cartridge. FIG. 23(E)and FIG. 23(F) shows the actuator 106 and around the actuator 106, andthe equivalent circuit of the actuator 106 when there is no ink in theink cartridge.

The actuator 106 includes abase plate 178, a vibrating plate 176, apiezoelectric layer 160, an upper electrode 164 and a lower electrode166, an upper electrode terminal 168, a lower electrode terminal 170,and a supplementary electrode 172. The base plate 178 has a circularshape opening 161 on approximately its center. The vibrating plate 176is provided on one of the face, which is called as “right side” infollowing, of the base plate 178 such as to cover the opening 161. Thepiezoelectric layer 160 is disposed on right side of the surface of thevibrating plate 176. The upper electrode 164 and the lower electrode 166sandwich the piezoelectric layer 160 from both sides. The upperelectrode terminal 168 connects to the upper electrode 164 electrically.The lower electrode terminal 170 connects to the lower electrode 166electrically. The supplementary electrode 172 is disposed between theupper electrode 164 and the upper electrode terminal 168 and connectsboth of the upper electrode 164 and the upper electrode terminal 168.Each of the piezoelectric layer 160, upper electrode 164, and the lowerelectrode 166 has a circular portion as its main portion. Each of thecircular portion of the piezoelectric layer 160, the upper electrode164, and the lower electrode 166 form a piezoelectric element.

The vibrating plate 176 is formed on the right side of the surface ofthe base plate 178 to cover the opening 161. The cavity 162 is formed bythe portion of the vibrating plate 176, which faces the opening 161, andthe opening 161 of the on the surface of the base plate 178. The face ofthe base plate 178 which is opposite side of the piezoelectric element,called as “back side” in following, is faced with the liquid containerside. The cavity 162 is constructed such that the cavity 162 contactswith liquid. The vibrating plate 176 is mounted on the base plate 178such that the liquid does not leak to the right side of the surface ofthe base plate 178 even if the liquid enters inside the cavity 162.

The lower electrode 166 is located on the right side of the vibratingplate 176, that is, opposite side against the liquid container. Thelower electrode 166 is provided on the vibrating plate 176 such that thecenter of the circular portion of the lower electrode 166, which is amain portion of the lower electrode 166, and the center of the opening161 substantially matches. The area of the circular portion of the lowerelectrode 166 is set to be smaller than the area of the opening 161. Thepiezoelectric layer 160 is formed on the right side of the surface ofthe lower electrode 166 such that the center of the circular portion andthe center of the opening 161 substantially match. The area of thecircular portion of the piezoelectric layer 160 is set to be smallerthan the area of the opening 161 and larger than the area of thecircular portion of the lower electrode 166.

The upper electrode 164 is formed on the right side of the surface ofthe piezoelectric layer 160 such that the center of the circularportion, which is a piezoelectric layer 160, and the center of theopening 161 substantially match. The area of the circular portion of theupper electrode 164 is set to be smaller than the area of the circularportion of the opening 161 and the piezoelectric layer 160 and largerthan the area of the circular portion of the lower electrode 166.

Therefore, the main portion of the piezoelectric layer 160 has astructure to be sandwiched by the main portion of the upper electrode164 and the main portion of the lower electrode each from right sideface and back side face, and thus the main portion of the piezoelectriclayer 160 can effectively drive and deform the piezoelectric layer 160.The circular portion, which is a main portion of each of thepiezoelectric layer 160, the upper electrode 164, and the lowerelectrode 166, forms the piezoelectric element in the actuator 106. Asexplained above, the electric element contacts with the vibrating plate.Within the circular portion of the upper electrode 164, circular portionof the piezoelectric layer 160, the circular portion of the lowerelectrode, and the opening 161, the opening 161 has the largest area. Bythis structure, the vibrating region which actually vibrates within thevibrating plate is determined by the opening 161. Furthermore, each ofthe circular portion of the upper electrode 164 and the circular portionof the piezoelectric layer 160 and the circular portion of the lowerelectrode has smaller area than the area of the opening 161. Thevibrating plate becomes easily vibrate. Within the circular portion ofthe lower electrode 166 and the circular portion of the upper electrode164 which connects to the piezoelectric layer 160 electrically, thecircular portion of the lower electrode 166 is smaller than the circularportion of the upper electrode 164. Therefore, the circular portion ofthe lower electrode 166 determines the portion which generates thepiezoelectric effect within the piezoelectric layer 160.

The center of the circular portion of the piezoelectric layer 160, theupper electrode 164, and the lower electrode 166, which form thepiezoelectric element, substantially match to the center of the opening161. Moreover, the center of the circular shape opening 161, whichdetermines the vibrating section of the vibrating plate 176, is providedon the approximately center of the actuator 106. Therefore, the centerof the vibrating section of the actuator 106 matches to the center ofthe actuator 106. Because the main portion of the piezoelectric elementand the vibrating section of the vibrating plate 176 have a circularshape, the vibrating section of the actuator 106 is symmetrical about acenter of the actuator 106.

Because the vibrating section is symmetrical about a center of theactuator 106, the excitation of the unnecessary vibration occurred owingto the asymmetric structure can be prevented. Therefore, the accuracy ofdetecting the resonant frequency increases. Furthermore, because thevibrating section is symmetric about the center of the actuator 106, theactuator 106 is easy to manufacture, and thus the unevenness of theshape for each of the piezoelectric element can be decreased. Therefore,the unevenness of the resonant frequency for each of the piezoelectricelement 174 decreases. Furthermore, because the vibrating section has anisotropic shape, the vibrating section is difficult to be influenced bythe unevenness of the fixing during the bonding process. That is, thevibrating section is bonded to the liquid container uniformly.Therefore, the actuator 106 is easy to assemble to the liquid container.

Furthermore, because the vibrating section of the vibrating plate 176has a circular shape, the lower resonant mode, for example, the primaryresonant mode dominates on the resonant mode of the residual vibrationof the piezoelectric layer 160, and thus the single peak appears on theresonant mode. Therefore, the peak and the noise can be distinguishedclearly so that the resonant frequency can be clearly detected.Furthermore, the accuracy of the detection of the resonant frequency canbe further increased by enlarge the area of the vibrating section of thecircular shape vibrating plate 176 because the difference of theamplitude of the counter electromotive force and the difference of theamplitude of the resonant frequency occurred by whether the liquidexists inside the liquid container increase.

The displacement generated by the vibration of the vibrating plate 176is larger than the displacement generated by the vibration of the baseplate 178. The actuator 106 has a two layers structure that isconstituted by the base plate 178 having a small compliance which meansit is difficult to be displaced by the vibration, and the vibratingplate 176 having a large compliance which means it is easy to bedisplaced by the vibration. By this two layers structure, the actuator106 can be reliably fixed to the liquid container by the base plate 178and at the same time the displacement of the vibrating plate 176 by thevibration can be increased. Therefore, the difference of the amplitudeof the counter electromotive force and the difference of the amplitudeof the resonant frequency depended on whether the liquid exists insidethe liquid container increases, and thus the accuracy of the detectionof the resonant frequency increases. Furthermore, because the complianceof the vibrating plate 176 is large, the attenuation of the vibrationdecreases so that the accuracy of the detection of the resonantfrequency increases. The node of the vibration of the actuator 106locates on the periphery of the cavity 162, that is, around the marginof the opening 161.

The upper electrode terminal 168 is formed on the right side of thesurface of the vibrating plate 176 to be electrically connected to theupper electrode 164 through the supplementary electrode 172. The lowerelectrode terminal 170 is formed on the right side of the surface of thevibrating plate 176 to be electrically connected to the lower electrode166. Because the upper electrode 164 is formed on the right side of thepiezoelectric layer 160, there is a difference in depth that is equal tothe sum of the thickness of the piezoelectric layer 160 and thethickness of the lower electrode 166 between the upper electrode 164 andthe upper electrode terminal 168. It is difficult to fill thisdifference in depth only by the upper electrode 164, and even it ispossible to fill the difference in depth by the upper electrode 164, theconnection between the upper electrode 164 and the upper electrodeterminal 168 becomes weak so that the upper electrode 164 will be cutoff. Therefore, this embodiment uses the supplementary electrode 172 asa supporting member to connects the upper electrode 164 and the upperelectrode terminal 168. By this supplementary electrode 172, both of thepiezoelectric layer 160 and the upper electrode 164 are supported by thesupplementary electrode 172, and thus the upper electrode 164 can havedesired mechanical strength, and also the upper electrode 164 and theupper electrode terminal 168 can be firmly connected.

The piezoelectric element and the vibrating section which faces to thepiezoelectric element within the vibrating plate 176 constitute thevibrating section which actually vibrates in the actuator 106. Moreover,it is preferable to form the actuator 106 in one body by firing togetherthe member included in the actuator 106. By forming the actuator 106 asone body, the actuator 106 becomes easy to be handled. Further, thevibration characteristic increases by increasing the strength of thebase plate 178. That is, by increasing the strength of the base plate178, only the vibrating section of the actuator 106, vibrates, and theportion other than the vibrating section of the actuator 106 does notvibrates. Furthermore, the prevention of the vibration of the portionother than the vibrating section of the actuator 106 can be achieved byincreasing the strength of the base plate 178 and at the same timeforming the actuator 106 as thinner and smaller as possible and formingthe vibrating plate 176 as thinner as possible.

It is preferable to use lead zirconate titanate (PZT), lead lanthanumzirconate titanate (PLZT), or piezoelectric membrane without using leadas a material for the piezoelectric layer 160. It is preferable to usezirconia or alumina as a material of the base plate 178. Furthermore, itis preferable to use same material as base plate 178 for a material ofvibrating plate 176. The metal such as gold, silver, copper, platina,aluminum, and nickel having a electrical conductivity can be used forthe material of the upper electrode 164, the lower electrode 166, theupper electrode terminal 168, and the lower electrode terminal 170.

The actuator 106 constructed as explained above can be applied to thecontainer which contains liquid. For example, the actuator 106 can bemounted on an ink cartridge used for the ink jet recording apparatus, anink tank, or a container which contains washing liquid to wash therecording head.

The actuator 106 shown in the FIG. 22 and FIG. 23 is mounted on thepredetermined position on the liquid container so that the cavity 162can contact with the liquid contained inside the liquid container. Whenthe liquid container is filled with liquid sufficiently, the inside andoutside of the cavity 162 is filled with liquid. On the other hand, ifthe liquid inside liquid container consumed and the liquid leveldecreased under the mounting position of the actuator, there areconditions that liquid does not exit inside the cavity 162 or thatliquid is remained only in the cavity 162 and air exits on outside thecavity 162. The actuator 106 detects at least the difference in theacoustic impedance occurred by this change in condition. By thisdetection of the difference in acoustic impedance, the actuator 106 candetects the whether the liquid is sufficiently filled in the liquidcontainer or liquid is consumed more than predetermined level.Furthermore, the actuator 106 can detects the type of the liquid insidethe liquid container.

The principle of the detection of the liquid level by the actuator willbe explained.

To detect the acoustic impedance of a medium, an impedancecharacteristic or an admittance characteristic is measured. To measurethe impedance characteristic or the admittance characteristic, forexample, transmission circuit can be used. The transmission circuitapplies a constant voltage on the medium and measure a current flowthrough the medium with changing a frequency. The transmission circuitprovides a constant current to the medium and measures a voltage appliedon the medium with changing a frequency. The change in current value andthe voltage value measured at the transmission circuit shows the changein acoustic impedance. Furthermore, the change in a frequency fm, whichis a frequency when the current value or the voltage value becomesmaximum or minimum, also shows the change in acoustic impedance.

Other than method shown above, the actuator can detects the change inthe acoustic impedance of the liquid using the change only in theresonant frequency. The piezoelectric element, for example, can be usedin a case of using the method of detecting the resonant frequency bymeasuring the counter electromotive force generated by the residualvibration, which is remained in the vibrating section after thevibration of the vibrating section of the actuator, as a method of usingthe change in the acoustic impedance of the liquid. The piezoelectricelement is element which generates the counter electromotive force byresidual vibration remained in the vibrating section of the actuator.The magnitude of the counter electromotive force changes with theamplitude of the vibrating section of the actuator. Therefore, thelarger the amplitude of the vibrating section of the actuator, theeasier to detect the resonant frequency. Moreover, depends on thefrequency of the residual vibration at the vibrating section of theactuator, the period, on which the magnitude of the counterelectromotive force changes, changes. Therefore, the frequency of thevibrating section of the actuator corresponds to the frequency of thecounter electromotive force. Here, the resonant frequency means thefrequency when the vibrating section of the actuator and the medium,which contacts to the vibrating section, are in a resonant condition.

To obtain the resonant frequency fs, the waveform obtained by measuringthe counter electromotive force when the vibrating section and themedium are in resonant condition is Fourier transformed. Because thevibration of the actuator is not a displacement for only one direction,but the vibration involves the deformation such as deflection andextension, the vibration has various kinds of frequency including theresonant frequency fs. Therefore, the resonant frequency fs is judged byFourier transforming the waveform of the counter electromotive forcewhen the piezoelectric element and the medium are in the resonantcondition and then specifying the most dominating frequency components.

The frequency fm is a frequency when the admittance of the medium ismaximum or the impedance is minimum. The frequency fm is different fromthe resonant frequency fs with little value because of the dielectricloss and the mechanical loss. However, the frequency fm is generallyused as substitution for resonant frequency because it needs time forderiving the resonant frequency fs from the frequency fm which isactually measured. By inputting output of the actuator 106 to thetransmission circuit, the actuator 106 can at least detect the acousticimpedance.

It is proved by the experiment that there is almost no differences withthe resonant frequency obtained by the method, which measures thefrequency fm by measuring the impedance characteristic and admittancecharacteristic of the medium, and the method, which measures theresonant frequency fs by measuring the counter electromotive forcegenerated by the residual vibration at the vibrating section of theactuator.

The vibrating region of the actuator 106 is a portion which constitutesthe cavity 162 that is determined by the opening 161 within thevibrating plate 176. When liquid is sufficiently filled in the liquidcontainer, liquid is filled in the cavity 162, and the vibrating regioncontacts with liquid inside the liquid container. When liquid does notexists in the liquid container sufficiently, the vibrating regioncontacts with the liquid which is remained in the cavity inside theliquid container, or the vibrating region does not contacts with theliquid but contacts with the gas or vacuum.

The cavity 162 is provided on the actuator 106 of the present invention,and it can be designed that the liquid inside the liquid containerremains in the vibrating region of the actuator 106 by the cavity 162.The reason will be explained as follows.

Depends on the mounting position and mounting angle of the actuator 106on the liquid container, there is a case in which the liquid attaches tothe vibrating region of the actuator even the liquid level in the liquidcontainer is lower than the mounting position of the actuator. When theactuator detects the existence of the liquid only from the existence ofthe liquid on the vibrating region, the liquid attached to the vibratingregion of the actuator prevents the accurate detection of the existenceof the liquid. For example, If the liquid level is lower than themounting position of the actuator, and the drop of the liquid attachesto the vibrating region by the waving of the liquid caused by theshaking of the liquid container caused by the movement of the carriage,the actuator 106 will misjudges that there is enough liquid in theliquid container. In this way, the malfunction can be prevented by usingthe actuator having cavity.

Furthermore, as shown in FIG. 23(E), the case when the liquid does notexit in the liquid container and the liquid of the liquid containerremains in the cavity, 162 of the actuator 106 is set as the thresholdvalue of the existence of the liquid. That is, if the liquid does notexist around the cavity 162, and the amount of the liquid in the cavityis smaller than this threshold value, it is judged that there is no inkin the liquid container. If the liquid exist around the cavity 162, andthe amount of the liquid is larger than this threshold value, it isjudged that there is ink in the liquid container. For example, when theactuator 106 is mounted on the side wall of the liquid container, it isjudged that there is no ink in the liquid container when the liquidlevel inside the liquid container is lower than the mounting position ofthe actuator 106, and it is judged that there is ink inside the liquidcontainer when the liquid level inside the liquid container is higherthan the mounting position of the actuator 106. By setting the thresholdvalue in this way, the actuator 106 can judge that there is no ink inthe liquid container even if the ink in the cavity is dried anddisappeared. Furthermore, the actuator 106 can judge that there is noink in the liquid container even if the ink attaches to the cavity againby shaking of the carriage after the ink in the cavity disappearsbecause the amount of the ink attaches to the cavity again does notexceed the threshold value.

The operation and the principle of detecting the liquid condition of theliquid container from the resonant frequency of the medium and thevibrating section of the actuator 106 obtained by measuring the counterelectromotive force will be explained reference to FIG. 22 and FIG. 23.A voltage is applied on each of the upper electrode 164 and the lowerelectrode 166 through the upper electrode terminal 168 and the lowerelectrode terminal 170. The electric field is generated on the portionof the piezoelectric layer 160 where the piezoelectric layer 160 issandwiched by the upper electrode 164 and the lower electrode 166. Bythis electric field, the piezoelectric layer 160 deforms. By thedeformation of the piezoelectric layer 160, the vibrating region withinthe vibrating plate 176 deflects and vibrates. For some period after thedeformation of the piezoelectric layer 160, the vibration withdeflection remains in the vibrating section of the actuator 106.

The residual vibration is a free oscillation of the vibrating section ofthe actuator 106 and the medium. Therefore, the resonant conditionbetween the vibrating section and the medium can be easily obtained byapplying the voltage of a pulse wave or a rectangular wave on thepiezoelectric layer 160. Because the residual vibration vibrates thevibrating section of the actuator 106, the residual vibration alsodeforms the piezoelectric layer 160. Therefore, the piezoelectric layer160 generates the counter electromotive force. This counterelectromotive force is detected through the upper electrode 164, thelower electrode 166, the upper electrode terminal 168, and the lowerelectrode terminal 170. Because the resonant frequency can be specifiedby this detected counter electromotive force, the liquid consumptionstatus in the liquid container can be detected.

Generally, the resonant frequency fs can be expressed as following.fs=1/(2*π*(M*Cact)^(1/2)  (1)where M denotes the sum of an inertance of the vibrating section Mactand an additional inertance M′; Cact denotes a compliance of thevibrating section.

FIG. 22(C) shows a cross section of the actuator 106 when the ink doesnot exist in the cavity in the present embodiment. FIG. 23(A) and FIG.23(B) shows the equivalent circuit of the vibrating section of theactuator 106 and the cavity 162 when the ink does not exist in thecavity.

The Mact is obtained by dividing the product of the thickness of thevibrating section and the density of the vibrating section by the areaof the vibrating section. Furthermore, as shown in the FIG. 23(A), theMact can be expressed as following in detail.Mact=Mpzt+Melectrodel+Melectrode2+Mvib  (2)Here, Mpzt is obtained by dividing the product of the thickness of thepiezoelectric layer 160 in the vibrating section and the density of thepiezoelectric layer 160 by the area of the piezoelectric layer 160.Melectrode1 is obtained by dividing the product of the thickness of theupper electrode 164 in the vibrating section and the density of theupper electrode 164 by the area of the upper electrode 164. Melectrode2is obtained by dividing the product of the thickness of the lowerelectrode 166 in the vibrating section and the density of the lowerelectrode 166 by the area of the lower electrode 166. Mvib is obtainedby dividing the product of the thickness of the vibrating plate 176 inthe vibrating section and the density of the vibrating plate 176 by thearea of the vibrating region of the vibrating plate 176. However each ofthe size of the area of the vibrating region of the piezoelectric layer160, the upper electrode 164, the lower electrode 166, and vibratingplate 176 have a relationship as shown above, the difference among eachof the area of the vibrating region is prefer to be microscopic toenable the calculation of the Mact from the thickness, density, and areaas whole of the vibrating section. Moreover, it is preferable that theportion other than the circular portion which is a main portion of eachof the piezoelectric layer 160, the upper electrode 164, and the lowerelectrode 166 is microscopic so that it can be ignored compared to themain portion. Therefore, Mact is sum of the inertance of the each of thevibrating region of the upper electrode 164, the lower electrode 166,the piezoelectric layer 160, and the vibrating plate 176 in the actuator106. Moreover, the compliance Cact is a compliance of the portion formedby the each of the vibrating region of the upper electrode 164, thelower electrode 166, the piezoelectric layer 160, and the vibratingplate 176.

FIG. 23(A), FIG. 23(B), FIG. 23(D), and FIG. 23(F) show the equivalentcircuit of the vibrating section of the actuator 106 and the cavity 162.In these equivalent circuits, Cact shows a compliance of the vibratingsection of the actuator 106. Each of the Cpzt, Celectrode1, Celectrode2,and Cvib shows the compliance of the vibrating section of thepiezoelectric layer 160, the upper electrode 164, the lower electrode166, and the vibrating plate 176. Cact can be shown as followingequation.1/Cact=(1/Cpzt)+(1/Celectrode1)+(1/Celectrode2)+(1/Cvib)  (3)

From the equation (2) and (3), FIG. 23(A) can be expressed as FIG.23(B).

The compliance Cact shows the volume which can accept the medium by thedeformation generated by the application of the pressure on the unitarea of the vibrating section. In other words, the compliance Cact showsthe easiness to be deformed.

FIG. 23(C) shows the cross section of the actuator 106 when the liquidis sufficiently filled in the liquid container, and the periphery of thevibrating region of the actuator 106 is filled with the liquid. The MImax shown in FIG. 23(C) shows the maximum value of the additionalinertance when the liquid is sufficiently filled in the liquidcontainer, and the periphery of the vibrating region of the actuator 106is filled with the liquid. The M′max can be expressed asM′max=(π*ρ/(2*k ³))*(2*(2*k*a)³/(3*π))/(π*a ²)²  (4)where a denotes the radius of the vibrating section; ρ denotes thedensity of the medium; and k denotes the wave number. The equation (4)applies when the vibrating region of the actuator 106 is circular shapehaving the radius of “a”. The additional inertance M′ shows the quantitythat the mass of the vibrating section is increased virtually by theeffect of the medium which exists around the vibrating section.

As shown in equation (4), the M′max can changes significantly by theradius of the vibrating section “a” and the density of the medium ρ.

The wave number k can be expressed by following equation.k=2*π*fact/c  (5)where fact denotes the resonant frequency of the vibrating section whenthe liquid does not contact with the vibrating section; and c denotesthe speed of the sound propagate through the medium.

FIG. 23(D) shows an equivalent circuit of the vibrating section of theactuator 106 and the cavity 162 as in the case of FIG. 23(C) when theliquid is sufficiently filled in the liquid container, and the peripheryof the vibrating region of the actuator 106 is filled with the liquid.

FIG. 23(E) shows the cross section of the actuator 106 when the liquidin the liquid container is consumed, and there is no liquid around thevibrating region of the actuator 106, and the liquid remains in thecavity 162 of the actuator 106. The equation (4) shows the maximuminertance M′max determined by such as the ink density ρ when the liquidcontainer is filled with the liquid. On the other hand, if the liquid inthe liquid container is consumed and liquid existed around the vibratingsection of the actuator 106 becomes gas or vacuum with the liquidremaining in the cavity 162, the M′ can be expressed as followingequation.M′=ρ*t/S  (6)where t denotes the thickness of the medium related to the vibration; Sdenotes the area of the vibrating region of the actuator 106. If thisvibrating region is circular shape having a radius of “a”, the S can beshown as S=π*a². Therefore, the additional inertance M′ follows theequation (4) when the liquid is sufficiently filled in the liquidcontainer, and the periphery of the vibrating region of the actuator 106is filled with the liquid. The additional inertance M′ follows theequation (6) when the liquid in the liquid container is consumed, andthere is no liquid exits around the vibrating region of the actuator106, and the liquid is remained in the cavity 162.

Here, as shown in FIG. 23(E), let the additional inertance M′, when theliquid in the liquid container is consumed, and there is no liquid exitsaround the vibrating region of the actuator 106, and the liquid isremained in the cavity 162, as M′cav to distinguish with the additionalinertance M′max, which is the additional inertance when the periphery ofthe vibrating region of the actuator 106 is filled with the liquid.

FIG. 23(F) shows an equivalent circuit of the vibrating section of theactuator 106 and the cavity 162 in the case of FIG. 23(E) when theliquid in the liquid container is consumed, and there is no liquidaround the vibrating region of the actuator 106, and the liquid remainsin the cavity 162 of the actuator 106.

Here, the parameters related to the status of the medium are density ofthe medium ρ and the thickness of the medium t in equation (6). When theliquid is sufficiently filled in the liquid container, the liquidcontacts with the vibrating section of the actuator 106. When the liquidis insufficiently filled in the liquid container, the liquid is remainedin the cavity, or the gas or vacuum contacts with the vibrating sectionof the actuator 106. If let the additional inertance during the processof the shifting from the M′max of FIG. 23(C) to the M′var of FIG. 23(E)when the liquid around the actuator 106 is consumed, because thethickness of the medium t changes according to the containing status ofthe liquid in the liquid container, the additional inertance M′varchanges, and resonant frequency also changes. Therefore, the existenceof the liquid in the liquid container can be detected by specify theresonant frequency. Here, if let t=d, as shown in FIG. 23(E) and usingthe equation (6) to express the m′cav, the equation (7) can be obtainedby substituting the thickness of the cavity “d” into the “t” in theequation (6).M′cav=ρ*d/S  (7)

Moreover, if the medium are different types of liquid with each other,the additional inertance M′ changes and resonant frequency fs alsochanges because the density ρ is different according to the differenceof the composition. Therefore, the types of the liquid can be detectedby specifying the resonant frequency fs. Moreover, when only one of theink or air contacts with the vibrating section of the actuator 106, andthe ink and air is not existing together, the difference in M′ can bedetected by calculating the equation (4).

FIG. 24(A) is a graph which shows the relationship between the inkquantity inside the ink tank and the resonant frequency fs of the inkand the vibrating section. Here, the case for the ink will be explainedas an example of the liquid. The vertical axis shows the resonantfrequency fs, and the horizontal axis shows the ink quantity. When theink composition is constant, the resonant frequency increases accordingto the decreasing of the ink quantity.

When ink is sufficiently filled in the ink container, and ink is filledaround the vibrating region of the actuator 106, the maximum additionalinertance M′max becomes the value shown in the equation (4). When theink is consumed, and there is no ink around the vibrating region of theactuator 106, and the ink remains in the cavity 162, the additionalinertance M′var is calculated by the equation (6) based on the thicknessof the medium t. Because the “t” used in the equation (6) is thethickness of the medium related to the vibration, the process duringwhich the ink is consumed gradually can be detected by forming the “d”(refer to FIG. 22(B)) of the cavity 162 of the actuator 106 as small aspossible, that is, forming the thickness of the base plate 178 assufficiently thinner as possible (refer to FIG. 23(C)). Here, let thet-ink as the thickness of the ink involved with the vibration, andt-ink-max as the t-ink when the additional inertance is M′max. Forexample, the actuator 106 is mounted on the bottom of the ink cartridgehorizontally to the surface of the ink. If ink is consumed, and the inklevel becomes lower than the height t-ink-max from the actuator 106, theM′var gradually changes according to the equation (6), and the resonantfrequency fs gradually changes according to the equation (1). Therefore,until the ink level is within the range of “t”, the actuator 106 cangradually detect the ink consumption status.

Furthermore, by enlarge or lengthen the vibrating section of theactuator 106 and arrange the actuator 106 along a lengthwise direction,the “S” in the equation (6) changes according to the change of ink levelwith ink consumption. Therefore, the actuator 106 can detect the processwhile the ink is gradually consumed. For example, the actuator 106 ismounted on the side wall of the ink cartridge perpendicularly to the inksurface. When the ink is consumed and the ink level reaches to thevibrating region of the actuator 106, because the additional inertanceM′ decreases with the decreasing of the ink level, the resonantfrequency fs gradually increases according to the equation (1).Therefore, unless the ink level is within the range of the radius 2 a ofthe cavity 162 (refer to FIG. 23(C)), the actuator 106 can graduallydetect the ink consumption status.

The curve X in FIG. 24(A) shows the relationship between the inkquantity contained inside of the ink tank and the resonant frequency fsof the ink and the vibrating section when the vibrating region of theactuator 106 is formed sufficiently large or long. It can be understandthat the resonant frequency fs of the ink and vibrating sectiongradually changes with the decrease of the ink quantity inside the inktank.

In detail, the case when the actuator 106 can detect the process of thegradual consumption of the ink is the case when the liquid and gashaving different density with each other are existed together and alsoinvolved with vibration. According to the gradual consumption of theink, the liquid decreases with increasing of the gas in the mediuminvolved with the vibration around the vibrating region of the actuator106. For example, the case when the actuator 106 is mounted on the inkcartridge horizontally to the ink surface, and t-ink is smaller than thet-ink-max, the medium involved with the vibration of the actuator 106includes both of the ink and the gas. Therefore, the following equation(8) can be obtained if let the area of the vibrating region of theactuator 106 as S and express the status when the additional inertanceis below M′max in the equation (4) by additional mass of the ink and thegas.M′=M′air+M′ink=ρair*t-air/S+ρink*t-ink/S  (8)where M′max is an inertance of an air; M′ink is an inertance of an ink;ρ air is a density of an air; ρ ink is a density of an ink; t-air is thethickness of the air involved with the vibration; and t-ink is thethickness of the ink involved with the vibration. In case when theactuator 106 is mounted on the ink cartridge approximately horizontallyto the ink surface, the t-air increases and the t-ink decreases with theincrease of the gas and the decrease of the ink within the mediuminvolved with the vibration around the vibrating region of the actuator106. The additional inertance M′ gradually decreases, and the resonantfrequency gradually increases by above changes of the t-air and thet-ink. Therefore, the ink quantity remained inside the ink tank or theink consumption quantity can be detected. The equation (7) depends onlyon the density of the liquid because of the assumption that the densityof the air is small compare to the density of the liquid so that thedensity of the air can be ignored.

When the actuator 106 is provided on the ink cartridge substantiallyperpendicular to the ink surface, the status can be expressed as theequivalent circuit, not shown in the figure, on which the region, wherethe medium involved with the vibration of the actuator 106 is ink only,and the region, where the medium involved with the vibration of theactuator 106 is gas, can be expressed as parallel circuit. If let thearea of the region where the medium involved with the vibration of theactuator 106 is ink only as Sink, and let the area of the region wherethe medium involved with the vibration of the actuator 106 is gas onlyas Sair, the following equation (9) can be obtained.1/M′=1/M′air+1/M′ink=Sair/(ρ air * t-air)+Sink/(ρ ink * t-ink)  (9)

The equation (9) can be applied when the ink is not held in the cavityof the actuator 106. The case when the ink is held in the cavity can becalculated using the equation (7), (8), and (9).

In the case when the thickness of the base plate 178 is thick, that is,the depth of the cavity 162 is deep and d is comparatively close to thethickness of the medium t-ink-max, or in the case when using actuatorhaving a very small vibrating region compared to height of the liquidcontainer, the actuator does not detect the process of the gradualdecrease of the ink but actually detects whether the ink level is higheror lower than the mounting position of the actuator. In other words, theactuator detects the existence of the ink at the vibrating region of theactuator. For example, the curve Y in FIG. 24(A) shows the relationshipbetween the ink quantity in the ink tank and the resonant frequency fsof the vibrating section when the vibrating section is small circularshape. The curve Y shows that the resonant frequency fs of the ink andthe vibrating section changes extremely during the range of change ofink quantity Q, which corresponds to the status before and after the inklevel in the ink tank passes the mounting position of the actuator. Bythis changes of the resonant frequency fs, it can be detected whetherthe ink quantity remained in the ink tank is more than the predeterminedquantity.

The method of using the actuator 106 for detecting the existence of theliquid is more accurate than the method which calculates the quantity ofink consumption by the software because the actuator 106 detects theexistence of the ink by directly contacting with the liquid.Furthermore, the method using an electrode to detects the existence ofthe ink by conductivity is influenced by the mounting position to theliquid container and the ink type, but the method using the actuator 106to detects the existence of the liquid does not influenced by themounting position to the liquid container and the ink type. Moreover,because both of the oscillation and detection of the existence of theliquid can be done by the single actuator 106, the number of the sensormounted on the liquid container can be reduced compare to the methodusing separate sensor for oscillation and the detection of the existenceof the liquid. Therefore, the liquid container can be manufactured at alow price. Furthermore, the sound generated by the actuator 106 duringthe operation of the actuator 106 can be reduced by setting thevibrating frequency of the piezoelectric layer 160 out of the audiofrequency.

FIG. 24(B) shows the relationship between the density of the ink and theresonant frequency fs of the ink and the vibrating section of the curveY shown in FIG. 24(A). Ink is used as an example of liquid. As shown inFIG. 24(B), when ink density increases, the resonant frequency fsdecreases because the additional inertance increases. In other words,the resonant frequency fs are different with the types of the ink.Therefore, By measuring the resonant frequency fs, it can be confirmedwhether the ink of a different density has been mixed together duringthe re-filling of the ink to the ink tank.

Therefore, the actuator 106 can distinguish the ink tank which containsthe different type of the ink.

The condition when the actuator 106 can accurately detects the status ofthe liquid will be explained in detail in following. The case is assumedthat the size and the shape of the cavity is designed so that the liquidcan be remained in the cavity 162 of the actuator 106 even when theliquid inside the liquid container is empty. The actuator 106 can detectthe status of the liquid even when the liquid is not filled in thecavity 162 if the actuator 106 can detect the status of the liquid whenthe liquid is filled in the cavity 162.

The resonant frequency fs is a function of the inertance M. Theinertance M is a sum of the inertance of the vibrating section Mact andthe additional inertanceM′. Here, the additional inertance M′ has therelationship with the status of the liquid. The additional inertance M′is a quantity of a virtual increase of a mass of the vibrating sectionby the effect of the medium existed around the vibrating section. Inother words, the additional inertance M′ is the amount of increase ofthe mass of the vibrating section which is increased by the vibration ofthe vibrating section that virtually absorbs the medium.

Therefore, when the M′cav is larger than the M′max in the equation (4),all the medium which is virtually absorbed is the liquid remained in thecavity 162. Therefore, the status when the M′cav is larger than theM′max is same with the status that the liquid container is fill withliquid. The resonant frequency fs does not change because the MI doesnot change in this case. Therefore, the actuator 106 cannot detect thestatus of the liquid in the liquid container.

On the other hand, if the M′cav is smaller than the M′max in theequation (4), the medium which is virtually absorbed is the liquidremained in the cavity 162 and the gas or vacuum in the liquidcontainer. In this case, because the M′ changes, which is different withthe case when the liquid is filled in the liquid container, the resonantfrequency fs changes. Therefore, the actuator 106 can detect the statusof the liquid in the liquid container.

The condition whether the actuator 106 can accurately detect the statusof the liquid is that the M′cav is smaller than the M′max when theliquid is remained in the cavity 162 of the actuator 106, and the liquidcontainer is empty. The condition M′max>M′cav, on which the actuator 106can accurately detect the status of the liquid, does not depend on theshape of the cavity 162.

Here, the M′cav is the mass of the liquid of the volume which issubstantially equal to the volume of the cavity 162. Therefore, thecondition, which can detect the status of the liquid accurately, can beexpressed as the condition of the volume of the cavity 162 from theinequality M′max>M′cav. For example, if let the radius of the opening161 of the circular shaped cavity 162 as “a” and the thickness of thecavity 162 as “d”, then the following inequality can be obtained.M′max>ρ*d/πa ²  (10)By expanding the inequality (10), the following condition can beobtained.a/d>3*π/8  (11)The inequality (10) and (11) are valid only when the shape of the cavity162 is circular. By using the equation when the M′max is not circularand substituting the area π a² with its area, the relationship betweenthe dimension of the cavity such as a width and a length of the cavityand the depth can be derived.

Therefore, if the actuator 106 has the cavity 162 which has the radiusof the opening 161 “a” and the depth of the cavity “d” that satisfy thecondition shown in inequality (11), the actuator 106 can detect theliquid status without malfunction even when the liquid container isempty and the liquid is remained in the cavity 162.

Because the additional inertance influences the acoustic impedancecharacteristic, it can be said that the method of measuring the counterelectromotive force generated in actuator 106 by residual vibrationmeasures at least the change of the acoustic impedance.

Furthermore, according to the present embodiment, the actuator 106generates the vibration, and the actuator 106 itself measures thecounter electromotive force in actuator 106 which is generated by theresidual vibration remained after the vibration of the actuator 106.However, it is not necessary for the vibrating section of the actuator106 to provide the vibration to the liquid by the vibration of theactuator 106 itself which is generated by the driving voltage. Even thevibrating section itself does not oscillates, the piezoelectric layer160 deflects and deforms by vibrates together with the liquid, whichcontacts with the vibrating section with some range. This residualvibration generates the counter electromotive force voltage in thepiezoelectric layer 160 and transfer this counter electromotive forcevoltage to the upper electrode 164 and the lower electrode 166. Thestatus of the liquid can be detected using this phenomenon. For example,in case of the ink jet recording apparatus, the status of the ink tankor the ink contained inside the ink tank can be detected using thevibration around the vibrating section of the actuator which isgenerated by the vibration generated by the reciprocating motion of thecarriage to scanning the print head during the printing operation.

FIG. 25(A) and FIG. 25(B) shows a waveform of the residual vibration ofthe actuator 106 and the measuring method of the residual vibration. Thechange of the ink level at the level of the mounting position of theactuator 106 in the ink cartridge can be detected by the change in thefrequency or the amplitude of the residual vibration remained after theoscillation of the actuator 106. In FIG. 25(A) and FIG. 25(B), thevertical axis shows the voltage of the counter electromotive forcegenerated by the residual vibration of the actuator 106, and thehorizontal axis shows the time. By the residual vibration of theactuator 106, the waveform of the analog signal of the voltage generatesas shown in FIG. 25(A) and FIG. 25(B). Then, the analog signal isconverted to a digital numerical value corresponding to the frequency ofthe signal.

In the example sown in FIG. 25(A) and FIG. 25(B), the existence of theink is detected by measuring the time during the generation of the fournumbers of pulses from the fourth pulse to the eighth pulse of theanalog signal.

In detail, after the actuator 106 oscillates, the number of the timeswhen the analog signal get across the predetermined reference voltageform the low voltage side to the high voltage side. The digital signalis set to be high while the analog signal becomes fourth counts to theeighth counts, and the time during fourth counts to the eighth counts ismeasured by predetermined clock pulse.

FIG. 25(A) shows the waveform when the ink level is above the level ofthe mounting position of the actuator 106. FIG. 25(B) shows the waveformwhen the ink level is below the level of the mounting position of theactuator 106. Comparing the FIG. 25(A) and FIG. 25(B), the time of theFIG. 25(A) during the fourth counts to the eighth counts is longer thanthe time of the FIG. 25(B). In other words, depends on the existence ofthe ink, the time from the fourth counts to the eighth counts isdifferent. By using this difference of the time, the consumption statusof the ink can be detected. The reason to count the analog signal fromthe fourth counts is to start the measurement of the time after thevibration of the actuator 106 becomes stable. It is only one of theexample of starting the measurement from fourth counts, but measurementcan be started from the desired counts.

The signals from the fourth counts to the eighth counts are detected,and the time from the fourth counts to the eighth counts is measured bythe predetermined clock pulse. By this measurement, the resonantfrequency can be obtained. The clock pulse is prefer to be a pulsehaving a same clock with the clock for controlling such as thesemiconductor memory device which is mounted on the ink cartridge. Itdoes not necessary to measure the time until the eighth counts, but thetime until the desired counts can be measured. In FIG. 25, the time fromthe fourth counts to the eighth counts is measured, however, the timeduring the different interval of the counts also can be detectedaccording to the circuit configuration which detects the frequency.

For example, when the ink quality is stable and the fluctuation of theamplitude of the peak is small, the resonant frequency can be detectedby detecting the time from the fourth counts to the sixth counts toincrease the speed of detection. Moreover, when the ink quality isunstable and the fluctuation of the amplitude of the pulse is large, thetime from the fourth counts to the twelfth counts can be detected todetect the residual vibration accurately.

Furthermore, as other embodiments, the wave number of the voltagewaveform of the counter electromotive force during the predeterminedperiod can be counted. More specifically, after the actuator 106oscillates, the digital signal is set to be high during thepredetermined period, and the number of the times when the analog signalis get across the predetermined reference voltage from the low voltageside to the high voltage side is counted. By measuring the count number,the existence of the ink can be detected.

Furthermore, it can be known by comparing FIG. 25(A) with FIG. 25(B),the amplitude of the waveform of the counter electromotive force isdifferent when the ink is filled in the ink cartridge and when the inkis not existed in the ink cartridge. Therefore, the ink consumptionstatus in the ink cartridge can be detected by measuring the amplitudeof the waveform of the counter electromotive force without calculatingthe resonant frequency. More specifically, for example, a referencevoltage is set between the peak point of the waveform of the counterelectromotive force of the FIG. 25(A) and the peak point of the waveformof the counter electromotive force of the FIG. 25(B). Then, after theactuator 106 oscillates, set the digital signal to be high at thepredetermined time. Then, if the waveform of the counter electromotiveforce get across the reference voltage, it can be judged that there isno ink in the ink cartridge. If the waveform of the counterelectromotive force does not get across the reference voltage, it can bejudged that there is ink in the ink cartridge.

FIG. 26 shows the manufacturing method of the actuator 106. A pluralityof the actuators 106, four numbers in the case of the FIG. 26, areformed as one body. The actuator 106 shown in FIG. 27 is manufactured bycutting the plurality of actuator 106, which is formed in one body asshown in FIG. 26, at each of the actuator 106. If the each of thepiezoelectric elements of the each of the plurality of the actuator 106,which is formed in one body as shown in FIG. 26, are circular shape, theactuator 106 shown in FIG. 22 can be manufactured by cutting theactuator 106, which is formed as one body, at each of actuator 106. Byforming a plurality of the actuator 106 in one body, a plurality ofactuator 106 can be manufactured effectively at the same time, and alsothe handling during the transportation becomes easy.

The actuator 106 has a thin plate or a vibrating plate 176, a base plate178, an elastic wave generating device or piezoelectric element 174, aterminal forming member or an upper electrode terminal 168, and aterminal forming member or a lower electrode terminal 170. Thepiezoelectric element 174 includes a piezoelectric vibrating plate or apiezoelectric layer 160, an upper electrode 164, and a lower electrode166. The vibrating plate 176 is formed on the top surface of the baseplate 178, and the lower electrode 166 is formed on the top surface ofthe vibrating plate 176. The piezoelectric layer 160 is formed on thetop surface of the lower electrode 166, and the upper electrode 164 isformed on the top surface of the piezoelectric layer 160. Therefore, themain portion of the piezoelectric layer 160 is formed by sandwiching themain portion of the piezoelectric layer 160 by the main portion of theupper electrode 164 and the main portion of the lower electrode 166 fromtop side and from bottom side.

A plurality of the piezoelectric element 174, four numbers in the caseof FIG. 26, is formed on the vibrating plate 176. The lower electrode166 is formed on the top surface of the vibrating plate 176. Thepiezoelectric layer 160 is formed on the top surface of the lowerelectrode 166, and the upper electrode 164 is formed on the top surfaceof the piezoelectric layer 160. The upper electrode terminal 168 and thelower electrode terminal 170 are formed on the end portion of the upperelectrode 164 and the lower electrode 166. The four numbers of theactuator 106 are used separately by cutting each of the actuator 106separately.

FIG. 27 shows a cross-section of a part of the actuator 106. The throughhole 178 a is formed on the face of the base plate 178 which faces withthe piezoelectric element 174. The through hole 178 a is sealed by thevibrating plate 176. The vibrating plate 176 is formed by the materialwhich has electric insulating characteristic such as alumina andzirconium oxide and also possible to be deformed elastically. Thepiezoelectric element 174 is formed on the vibrating plate 176 to facewith the through hole 178 a. The lower electrode 166 is formed on thesurface of the vibrating plate 176 so as to be extended to the onedirection, left direction in FIG. 28, from the region of the throughhole 178 a. The upper electrode 164 is formed on the surface of thepiezoelectric layer 160 so as to be extended to the opposite directionof the lower electrode 166, which is right direction in FIG. 28, fromthe region of the through hole 178 a. Each of the upper electrodeterminal 168 and the lower electrode terminal 170 is formed on thesurface of the each of supplementary electrode 172 and the lowerelectrode 166, respectively. The lower electrode terminal 170 with thelower electrode 166 electrically, and the upper electrode terminal 168contacts with the upper electrode 164 electrically through thesupplementary electrode 172 to deliver a signal between thepiezoelectric element and the outside of the actuator 106. The upperelectrode terminal 168 and the lower electrode terminal 170 has a heighthigher than the height of the piezoelectric element which is the sum ofthe height of the electrodes and the piezoelectric layer.

FIG. 29 shows the manufacturing method of the actuator 106 shown in FIG.26. First, a through hole 940 a is formed on a green sheet 940 byperforating the green sheet 940 by a press or laser processing. Thegreen sheet 940 becomes the base plate 178 after the burning process.The green sheet 940 is formed by the material such as ceramic material.Then, a green sheet 941 is laminated on the surface of the green sheet940. The green sheet 941 becomes the vibrating plate 176 after theburning process. The green sheet 941 is formed by the material such aszirconium oxide. Then, a conductive layer 942, the piezoelectric layer160, and a conductive layer 944 is formed on the surface of the greensheet 941 sequentially by the method such as printing. The conductivelayer 942 becomes the lower electrode 166, and the conductive layer 944becomes the upper electrode 164 after the burning process.

Next, the green sheet 940, the green sheet 941, the conductive layer942, the piezoelectric layer 160, and the conductive layer 944 are driedand burned. The spacer member 947 and 948 are provided on the greensheet 941 to raising the height of the upper electrode terminal 168 andthe lower electrode terminal 170 to be higher than the piezoelectricelement. The spacer member 947 and 948 is formed by printing the samematerial with the green sheet 940 and 941 or by laminating the greensheet on the green sheet 941. By this spacer member 947 and 948, thequantity of the material of the upper electrode terminal 168 and thelower electrode terminal 170, which is a noble metal, can be reduced.Moreover, because the thickness of the upper electrode terminal 168 andthe lower electrode terminal 170 can be reduced, the upper electrodeterminal 168 and the lower electrode terminal 170 can be accuratelyprinted to be a stable height.

If a connection part 944′, which is connected with the conductive layer944, and the spacer member 947 and 948 are formed at the same time whenthe conductive layer 942 is formed, the upper electrode terminal 168 andthe lower electrode terminal 170 can be easily formed and firmly fixed.Finally, the upper electrode terminal 168 and the lower electrodeterminal 170 are formed on the end region of the conductive layer 942and the conductive layer 944. During the forming of the upper electrodeterminal 168 and the lower electrode terminal 170, the upper electrodeterminal 168 and the lower electrode terminal 170 are formed to beconnected with the piezoelectric layer 160 electrically.

FIG. 30 shows the further other embodiment of the ink cartridge of thepresent invention. In the ink cartridge shown in FIG. 30, ink absorbingmember 74 is provided in the container 1 to face to the through hole 1c, which is provided inside the container 1, as a wave preventing wall.The actuator 70 is fixed to the bottom of the container 1 to face to thethrough hole 1 c. the ink absorbing member 74 prevents the wave orbubbles of ink inside the ink cartridge to enter into the through hole 1c. The ink absorbing member thereby prevents the wave or bubbles of inkto move close to the actuator 70 and attach to the actuator 70.

The ink absorbing member 74 is designed such that the hole diameter ofthe porous part 74 b around the ink supply port 2 is smaller than thehole diameter of the porous part 74 a around the actuator 70.Furthermore, the ink absorbing member 74 is designed such that thecapillary force of the porous part 74 b around the ink supply port 2 issmaller than the capillary force in a degree which holds ink.

Thereby, if the ink absorbing member 74 exposes from ink by consuming ofink inside the container 1, ink in the ink absorbing member 74 flows outfrom the ink absorbing member 74 by its own weight to the ink supplyport 2. If all the ink inside the container 1 consumed up, the inkabsorbing member 74 absorbs the ink remained in the through hole 1 c bythe capillary force. Therefore, ink is drained from the concave part ofthe through hole 1 c. Therefore, because the residual vibration of theactuator 70 changes at the ink end status, the timing of the ink end canbe further reliably detected.

Therefore, the ink absorbing member 74 can protect the actuator 70 fromthe wave of ink and also absorbs the ink remained in the through hole 1c to improve the accuracy of the ink end detection of the actuator 106.

FIG. 31 shows further other embodiment of the ink cartridge of thepresent invention. FIG. 31(A) is a cross sectional view of the bottompart of the ink cartridge of the present embodiment. The ink cartridgeof the present embodiment has a through hole 1 c on the bottom face 1 aof the container 1, which contains ink. The bottom part of the throughhole 1 c is closed by the actuator 650 and forms an ink storing part.The ink absorbing member 78 is provided around the inside the throughhole 1 c which is provided inside the container 1 and around the throughhole 1 c as a wave preventing wall. The ink absorbing member 78 has aink absorbing member 78 a which is provided inside the through hole 1 cand the ink absorbing member 78 b which is provided around the throughhole 1 c.

FIG. 31(B) shows a detailed cross section of the actuator 650 and thethrough hole 1 c shown in FIG. 31(A). FIG. 31(C) shows a plan view ofthe actuator 650 and the through hole 1 c shown in FIG. 31(B). Theactuator 650 has a vibrating plate 72 and a piezoelectric element 73which is fixed to the vibrating plate 72. The vibrating plate 72 can beelastically deformed and is ink resistant. In the present embodiment,the shape of the piezoelectric element 73 and the through hole 1 c islong and narrow rectangular, and both ends of which is circular shape.

FIG. 32 shows other embodiment of the through hole 1 c. In each of FIGS.32(A), (B), and (C), the left hand side of the figure shows the statusthat there is no ink K in the through hole 1 c, and the right hand sideof the figure shows the status that ink K is remained in the throughhole 1 c. In the embodiment of FIG. 31, the side face of the throughhole 1 c is formed as the vertical wall. In FIG. 32(A), the side face 1d of the through hole 1 c is slanted in vertical direction and openswith expanding to the outside. In FIG. 32(B), a stepped portion 1 e andif are formed on the side face of the through hole 1 c. The steppedportion 1 f, which is provided above the stepped portion 1 e, is widerthan the stepped portion 1 e. In FIG. 32(C), the through hole 1 c has agroove 1 g that extends to the direction in which ink is easilydischarged, that is, the direction to a ink supply port 2.

A wave preventing wall, not shown in the figure, is provided in thecontainer 1 such that the wave preventing wall faces to the actuator650.

According to the shape of the through hole 1 c shown in FIG. 32(A) to(C), the quantity of ink K in the ink storing part can be reduced.Therefore, because the M′cav can be smaller than the M′max explained inFIG. 22 and FIG. 23, the vibration characteristic of the actuator 650 atthe time of the ink end status can be greatly different with thevibration characteristic when enough quantity of ink K for printing isremained in the container 1, and thus the ink end status can be reliablydetected.

FIGS. 33(A) and (B) is a slant view of the further other embodiment ofthe actuator. FIG. 33(B) shows a part of a side cross section of the inkcartridge, on which an actuator 670 of the embodiment shown in FIG.33(A) is mounted. In the present embodiment, the actuator 670 comprisesa concave part forming base plate 80 and a piezoelectric element 82. Theconcave part 81 is formed on the one side of the face of the concavepart forming base plate 80 by the technique such as etching, andpiezoelectric element 82 is mounted on the other side of the face of theconcave part forming base plate 80. The bottom portion of the concavepart 81 operates as a vibrating region within the concave part formingbase plate 80. Therefore, the vibrating region of the actuator 670 isdetermined by the periphery of the concave part 81. Furthermore, theactuator 670 has the similar structure with the structure of theactuator 106 shown in FIG. 22, in which the base plate 178 and thevibrating plate 176 is formed as one body. Therefore, the manufacturingprocess during the manufacturing an ink cartridge can be reduced, andthe cost for manufacturing an ink cartridge also can be reduced. Theactuator 670 has a size which can be embedded into the through hole 1 cprovided on the container 1. By this embedding process, the concave part81 can operates as the cavity. The actuator 106 shown in FIG. 22 can beformed to be embedded into through hole 1 c as actuator 670 shown inFIG. 33. Moreover, the wave preventing wall 1192 u is provided nearbythe concave part 81 in the container 1 such that the wave preventingwall 1192 u faces to the actuator 670.

FIG. 34 shows a slant view of the other embodiment of the actuator. Theactuator 660 has packing 76 on the outside of the base plate, whichconstitutes the actuator 660, or the through hole 1 c of a mountingplate 72. Caulking holes 77 are formed on the outskirts of the actuator660. The actuator 660 is fixed to the container 1 through the caulkinghole 77 with caulking.

Furthermore, also in the present embodiment, the wave preventing wall,not shown in the figure, can be provided nearby the packing 76 such thatthe wave preventing wall faces to the actuator 670 as shown in FIG.33(B). If the wave preventing wall, not shown in the figure, is form ofa mesh or a material which pass through ink such as porous material, thewave preventing wall can be previously mounted on the periphery of thepacking 76. If the wave preventing wall is the member which pass throughink, the actuator 660 can detects ink. In this case, the wave preventingwall 1192 u is mounted on the ink cartridge together with the actuator670 as one body. Because the process of mounting the wave preventingwall on the ink cartridge is abbreviate, the manufacturing process isreduced, and the cycle time and cost of manufacturing the ink cartridgeare reduced.

FIGS. 35A, 35B and 35C show plan views of the through hole 1 c accordingto another embodiment. As shown respectively in FIGS. 35A, 35B and 35C,the plane shape of the through hole 1 c may be of arbitrary shapes suchas circular, rectangular, and triangle shape as long as the elastic wavegenerating device is capable of being mounted thereto.

FIG. 36 shows a slant view of the configuration that forms the actuator106 in one body as a mounting module 100. The module 100 is mounted onthe predetermined position of the container 1 of an ink cartridge. Themodule 100 is constituted to detect the ink consumption status in thecontainer 1 by detecting at least the change of acoustic impedance ofthe ink liquid. The module 100 of the present embodiment has a liquidcontainer mounting member 101 for mounting the actuator 106 to thecontainer 1. The liquid container mounting member 101 has a structurewhich mounts a cylindrical part 116 that contains the actuator 106 whichoscillates by the driving signal on a base mount 102, the plan of whichis substantially rectangular. Because the module 100 is constructed sothat the actuator 106 of the module 100 can not be contact from outsidewhen the module 100 is mounted on the ink cartridge, the actuator 106can be protected from outside contact. The top side of the edge of thecylindrical part 116 is chamfered so that the cylindrical part 116 canbe easily fit into the hole which is formed in the ink cartridge.

FIG. 37 shows an exploded view of the module 100 shown in FIG. 36 toshow the structure of the module 100. The module 100 includes a liquidcontainer mounting member 101 made from a resin and a piezoelectricdevice mounting member 105 which has a plate 110 and a concave part 113.Furthermore, the module 100 has a lead wire 104 a and 104 b, actuator106, and a film 108. Preferably, the plate 110 is made from a materialwhich is difficult to be rust such as stainless or stainless alloy. Theopening 114 is formed on the central part of the cylindrical part 116and the base mount 102 which are included in the liquid containermounting member 101 so that the cylindrical part 116 and the base mount102 can contain the lead wire 104 a and 104 b. The concave part 113 isformed on the central part of the cylindrical part 116 and the basemount 102 so that the cylindrical part 116 and the base mount 102 cancontain the actuator 106, the film 108, and the plate 110. The actuator106 is connected to the plate 110 through the film 108, and the plate110 and the actuator 106 are fixed to the liquid container mountingmember 101. Therefore, the lead wire 104 a and 104 b, the actuator 106,the film 108 and the plate 110 are mounted on the liquid containermounting member 101 as one body. Each of the lead wire 104 a and 104 btransfer a driving signal to piezoelectric layer by coupling with theupper electrode and the lower electrode 166 of the actuator 106, andalso transfer the signal of resonant frequency detected by the actuator106 to recording apparatus. The actuator 106 oscillates temporally basedon the driving signal transferred from the lead wire 104 a and 104 b.The actuator 106 vibrates residually after the oscillation and generatesa counter electromotive force by the residual vibration. By detectingthe vibrating period of the waveform of the counter electromotive force,the resonant frequency corresponding to the consumption status of theliquid in the liquid container can be detected. The film 108 bonds theactuator 106 and the plate 110 to seal the actuator 106. The film 108 ispreferably formed by such as polyolefin and bonded to the actuator 106and the plate 110 by heat sealing. By bonding the actuator 106 and theplate 110 with the film 108 face with face, the unevenness of thebonding on location decreases, and thus the portion other than thevibrating plate does not vibrate. Therefore, the change of the resonantfrequency before and after bonding the actuator 106 to plate 110 issmall.

The plate 110 is circular shape, and the opening 114 of the base mount102 is formed in cylindrical shape. The actuator 106 and the film 108are formed in rectangular shape. The lead wire 104, the actuator 106,the film 108, and the plate 110 can be attached to and removed from thebase mount 102. Each of the base mount 102, the lead wire 104, theactuator 106, the film 108, and the plate 110 is arranged symmetric withrespect to the central axis of the module 100. Furthermore, each of thecenters of the base mount 102, the actuator 106, the film 108, and theplate 110 is arranged substantially on the central axis of the module100.

The opening 114 of the base mount 102 is formed such that the area ofthe opening 114 is larger than the area of the vibrating region of theactuator 106. The through hole 112 is formed on the center of the plate110 where the vibrating section of the actuator 106 faces. As shown inFIG. 22 and FIG. 23, the cavity 162 is formed on the actuator 106, andboth of the through hole 112 and the cavity 162 forms ink storing part.The thickness of the plate 110 is preferably smaller than diameter ofthe through hole 112 to reduce the influence of the residual ink. Forexample, the depth of the through hole 112 is preferably smaller thanone third of the diameter of the through hole 112. The shape of thethrough hole 112 is substantially true circle and symmetric with respectto the central axis of the module 100. Furthermore, the area of thethrough hole 112 is larger than the area of opening of the cavity 162 ofthe actuator 106. The periphery of the shape of the cross-section of thethrough hole 112 can be tapered shape of stepped shape. The module 100is mounted on the side, top, or bottom of the container 1 such that thethrough hole 112 faces to the inside of the container 1. When the ink isconsumed, and the ink around the actuator 106 is exhausted, the resonantfrequency of the actuator 106 greatly changes. The change of the inklevel can thus be detected.

FIG. 38 shows the slant view of the other embodiments of the module. Thepiezoelectric device mounting member 405 is formed on the liquidcontainer mounting member 101 in the module 400 of the presentembodiment. The cylindrical part 403, which has a cylindrical shape, isformed on the base mount 102, which has a square shaped plan, the edgesof which are rounded, in the liquid container mounting member 401.Furthermore, the piezoelectric apparatus mounting member 405 includes aboard shaped element 405, which is set up on the cylindrical part 403,and a concave part 413. The actuator 106 is arranged on the concave part413 provided on the side face of the board shaped element 406. The topend of the board shaped element 406 is chamfered in predetermined angleso that the board shaped element is easy to fit into hole formed on theink cartridge when mounting the actuator 106 to ink cartridge.

FIG. 39 shows an exploded view of the module 400 shown in FIG. 38 toshow the structure of the module 400. As the module 100 shown in FIG.36, the module 400 includes a liquid container mounting member 401 and apiezoelectric device mounting member 405. The liquid container mountingmember 401 has the base mount 402 and the cylindrical part 403, and thepiezoelectric device mounting member 405 has the board shaped element406 and the concave part 413. The actuator 106 is connected to the plate410 and fixed to the concave part 413. The module 400 has a lead wire404 a and 404 b, actuator 106, and a film 408.

According to the present embodiment, the plate 410 is rectangular shape,and the opening 414 provided on the board shaped element 406 is formedin rectangular shape. The lead wire 404 a and 404 b, the actuator 106,the film 408, and the plate 410 can be attached to and removed from thebase mount 402. Each of the actuator 106, the film 408, and the plate410 is arranged symmetric with respect to the central axis which isextended to perpendicular direction to the plan of opening 414 and alsopass through the center of opening 414. Furthermore, each of the centersof the actuator 106, the film 408, and the plate 410 is arrangedsubstantially on the central axis of the opening 414.

The through hole 412 provided on the center of the plate 410 is formedsuch that the area of the through hole 412 is larger than the area ofthe opening of the cavity 162 of the actuator 106. The cavity 162 of theactuator 106 and the through hole 412 together forms ink storing part.The thickness of the plate 410 is preferably smaller than diameter ofthe through hole 412. For example, the thickness of the plate 410 issmaller than one third of the diameter of the through hole 412. Theshape of the through hole 412 is substantially true circle and symmetricwith respect to the central axis of the module 400. The shape of thecross-section of the periphery of the through hole 112 can be taperedshape or stepped shape. The module 400 can be mounted on the bottom ofthe container 1 such that the through hole 412 is arranged inside of thecontainer 1. Because the actuator 106 is arranged inside the container 1such that the actuator 106 extends in the vertical direction, thesetting of the timing of the ink end can be easily changed by changingthe height of the mounting position of the actuator 106 in the container1 by changing the height of the base mount 402.

FIG. 40 shows the further other embodiment of the module. As the module100 shown in FIG. 36, the module 500 of FIG. 40 includes a liquidcontainer mounting member 501 which has a base mount 502 and acylindrical part 503. Furthermore, the module 500 further has a leadwire 504 a and 504 b, actuator 106, a film 508, and a plate 510. Theopening 514 is formed on the center of the base mount 502, which isincluded in the liquid container mounting member 501, so that the basemount 502 can contain the lead wire 504 a and 504 b. The concave part513 is formed on the cylindrical part 503 so that the cylindrical part503 can contain the actuator 106, the film 508, and the plate 510. Theactuator 106 is fixed to the piezoelectric device mounting member 505through the plate 510. Therefore, the lead wire 504 a and 504 b, theactuator 106, the film 508, and the plate 510 are mounted on the liquidcontainer mounting member 501 as one body. The cylindrical part 503, thetop face of which is slanted in vertical direction, is formed on thebase mount which has a square shaped plan and the edges of which arerounded. The actuator 106 is arranged on the concave part 513 which isprovided on the top surface of the cylindrical part 503 that is slantedin vertical direction.

The top end of the module 500 is slanted, and the actuator 106 ismounted on this slanted surface. Therefore, if the module 500 is mountedon the bottom or the side of the container 1, the actuator 106 slants inthe vertical direction of the container 1. The slanting angle of the topend of the module 500 is substantially between 30 degree and 60 degreewith considering the detecting performance.

The module 500 is mounted on the bottom or the side of the container 1so that the actuator 106 can be arranged inside the container 1. Whenthe module 500 is mounted on the side of the container 1, the actuator106 is mounted on the container 1 such that the actuator 106 faces theupside, downside, or side of the container 1 with slanting. When themodule 500 is mounted on the bottom of the container 1, the actuator 106is preferable to be mounted on the container 1 such that the actuator106 faces to the ink supply port side of the container 1 with slanting.

FIG. 41 shows a cross-sectional view around the bottom of the container1 when the module 100 shown in FIG. 36 is mounted on the container 1.The module 100 is mounted on the container 1 so that the module 100penetrates through the side wall of the container 1. The O-ring 365 isprovided on the connection face of between the side wall of thecontainer 1 and the module 100 to seal between the module 100 and thecontainer 1. The module 100 is preferable to include the cylindricalpart as explained in FIG. 36 so that the module 100 can be sealed by theO-ring. By inserting the top end of the module 100 inside the container1, ink in the container 1 contacts with the actuator 106 through thethrough hole 112 of the plate 110. Because the resonant frequency of theresidual vibration of the actuator 106 is different depends on whetherthe circumference of the vibrating section of the actuator 106 is liquidor gas, the ink consumption status can be detected using the module 100.Furthermore, not only the module 100 can be mounted on the container 1and detect the existence of ink, but also the module 400 shown in FIG.38, module 500 shown in FIG. 40, or the module 700A and 700B shown inFIG. 42, and a mold structure 600 can be mounted on the container 1 anddetect the existence of the ink.

FIG. 42(A) shows the cross section of the ink container when mountingmodule 700B on the container 1. The present embodiment uses a module700B as an example of amounting structure. The module 700B is mounted onthe container 1 such that the liquid container mounting member 360protrude into the inside of the A through hole 370 is formed in themounting plate 350, and the through hole 370 faces to the vibratingsection of the actuator 106. Furthermore, a hole 382 is formed on thebottom wall of the module 700B, and a piezoelectric device mountingmember 363 is formed. The actuator 106 is arranged to close the one ofthe face of the hole 382. Therefore, ink contacts with the vibratingplate 176 through the hole 382 of the piezoelectric device mountingmember 363 and the through hole 370 of the mounting plate 350. The hole382 of the piezoelectric device mounting member 363 and the through hole370 of the mounting plate 350 together forms an ink storing part. Thepiezoelectric device mounting member 363 and the actuator 106 are fixedby the mounting plate 350 and the film material. The sealing structure372 is provided on the connection part of the liquid container mountingmember 360 and the container 1. The sealing structure 372 can be formedby the plastic material such as synthetic resin or O-ring. In FIG.42(A), the module 700B and the container 1 is separate body, however,the piezoelectric device mounting member can be constituted by a part ofthe container 1 as shown in FIG. 42(B).

The module 700B shown in FIG. 42 does not need to embed the lead wireinto the module as shown in FIG. 36 to FIG. 40. Therefore, the formingprocess becomes simple. Also, the exchange of the module 700B becomespossible so that the recycling of the module 700B also becomes possible.

There is possibility that the actuator 106 malfunctions by the contactof the ink which is dropped from a top face or a side face of thecontainer 1 with the actuator 106, the ink of which is attached to thetop face or the side face of the container 1 when the ink cartridge isshaken. However, because the liquid container mounting member 360 of themodule 700B protrudes into the inside of the container 1, the actuator106 does not malfunction by the ink dropped from the top face or theside face of the container 1.

Furthermore, the module 700B is mounted on the container 1 so that onlypart of the vibrating plate 176 and the mounting plate 350 are contactwith ink inside of the container 1 in the embodiment of FIG. 42(A). Theembedding of the electrode of the lead wire 104 a, 104 b, 404 a, 404 b,504 a, and 504 shown in FIG. 36 to FIG. 40 into the module becomesunnecessary for the embodiment shown in FIG. 42(A). Therefore, theforming process becomes simple. Also, the exchange of the actuator 106becomes possible so that the recycling of the actuator 106 also becomespossible.

FIG. 42((B) shows the cross section of the ink container when mountingactuator 106 on the container 1. A protecting member 361 is mounted onthe container separately with the actuator 106 in the ink cartridge ofthe embodiment shown in FIG. 42((B). Therefore, the protecting member361 and the actuator 106 is not one body as a module, and the protectingmember 361 thus can protect the actuator 106 not to be contact by theuser. A hole 380 which is provide on the front face of the actuator 106is arranged on the side wall of the container 1. The actuator 106includes the piezoelectric layer 160, the upper electrode 164, the lowerelectrode 166, the vibrating plate 176, and the mounting plate 350. Thevibrating plate 176 is formed on the mounting plate 350, and the lowerelectrode 166 is formed on the vibrating plate 176. The piezoelectriclayer 160 is formed on the top face of the lower electrode 166, and theupper electrode 164 is formed on the top face of the piezoelectric layer160.

Therefore, the main portion of the piezoelectric layer 160 is formed bysandwiching the main portion of the piezoelectric layer 160 by the mainportion of the upper electrode 164 and the lower electrode 166 from topand bottom. The circular portion, which is a main portion of each of thepiezoelectric layer 160, the upper electrode 164, and the lowerelectrode 166, forms a piezoelectric element. The piezoelectric elementis formed on the vibrating plate 176. The vibrating region of thepiezoelectric element and the vibrating plate 176 constitutes thevibrating section, on which the actuator 106 actuary vibrates. A throughhole 370 is provided on the mounting plate 350. Furthermore, a hole 380is formed on the side wall of the container 1.

Therefore, ink contacts with the vibrating plate 176 through the hole380 of the container 1 and the through hole 370 of the mounting plate350. The hole 380 of the container land the through hole 370 of themounting plate 350 together forms ink storing part.

Moreover, because the actuator 106 is protected by the protecting member361, the actuator 106 can be protected form the outside contact. Thebase plate 178 shown in FIG. 22 can be used instead of the mountingplate 350 in the embodiment shown in FIGS. 42(A) and (B).

FIG. 42(C) shows an embodiment that comprises a mold structure 600 whichincludes the actuator 106. In the present embodiment, a mold structure600 is used as one example of the mounting structure. The mold structure600 has the actuator 106 and a mold member 364. The actuator 106 and themold member 364 are formed in one body. The mold member 364 is formed bya plastic material such as silicon resin. The mold member 364 includes alead wire 362 in its inside. The mold member 364 is formed so that themold member 364 has two legs extended from the actuator 106. The end ofthe two legs of the mold member 364 are formed in a shape of hemisphereto liquid tightly fix the mold member 364 with container 1. The moldmember 364 is mounted on the container 1 such that the actuator 106protrudes into the inside of the container 1, and the vibrating sectionof the actuator 106 contacts with ink inside the container 1. The upperelectrode 164, the piezoelectric layer 160, and the lower electrode 166of the actuator 106 are protected from ink by the mold member 364.

Because the mold structure 600 shown in FIG. 42 does not need thesealing structure 372 between the mold member 364 and the container 1,the leaking of ink from the container 1 can be reduced. Moreover,because the mold structure 600 has a form that the mold structure 600does not protrude from the outside of the container 1, the moldstructure 600 can protect the actuator 106 from the outside contact.There is possibility that the actuator 106 malfunctions by the contactof the ink which is dropped from a top face or a side face of thecontainer 1 with the actuator 106, the ink of which is attached to thetop face or the side face of the container 1 when the ink cartridge isshaken. Because the mold member 364 of the mold structure 600 protrudesinto the inside of the container 1, the actuator 106 does notmalfunction by the ink dropped from the top face or the side face of thecontainer 1.

FIG. 43 shows an embodiment of an ink cartridge and an ink jet recordingapparatus which uses the actuator 106 shown in FIG. 22. A plurality ofink cartridges 180 is mounted on the ink jet recording apparatus whichhas a plurality of ink introducing members 182 and a holder 184 eachcorresponding to the each of ink cartridge 180, respectively. Each ofthe plurality of ink cartridges 180 contains different types of ink, forexample, different color of ink. The actuator 106, which detects atleast acoustic impedance, is mounted on the each of bottom of theplurality of ink cartridge 180. The residual quantity of ink in the inkcartridge 180 can be detected by mounting the actuator 106 on the inkcartridge 180.

Furthermore, the wave preventing wall, not shown in the figure, isprovided inside the ink cartridge 180 such that the wave preventing wallfaces to the actuator 106.

FIG. 44 shows a detail around the head member of the ink jet recordingapparatus. The ink jet recording apparatus has an ink introducing member182, a holder 184, a head plate 186, and a nozzle plate 188. A pluralityof nozzle 190, which jet out ink, is formed on the nozzle plate 188. Theink introducing member 182 has an air supply hole 181 and an inkintroducing inlet 183. The air supply hole 181 supplies air to the inkcartridge 180. The ink introducing inlet 183 introduces ink from the inkcartridge 180. The ink cartridge 180 has an air introducing inlet 185and an ink supply port 187. The air introducing inlet 185 introduces airfrom the air supply hole 181 of the ink introducing member 182. The inksupply port 187 supplies ink to the ink introducing inlet 183 of the inkintroducing member 182. By introducing air from the ink introducingmember 182 to the ink cartridge 180, the ink cartridge 180 acceleratesthe supply of ink from the ink cartridge 180 to the ink introducingmember 182.

Furthermore, the wave preventing wall, not shown in the figure, isprovided inside the ink cartridge 180 such that the wave preventing wallfaces to the actuator 106.

FIG. 45 shows other embodiment of the ink cartridge 180 shown in FIG.44. The actuator 106 is mounted on the bottom face 194 a, which isformed to be slanted in vertical direction, of the ink cartridge 180Ashown in the FIG. 45(A). A wave preventing wall 1192 v is provided onthe position where has the predetermined height from the bottom face ofthe inside the container 194 and also faces to the actuator 106 insidethe container 194 of the ink cartridge 180. Because the actuator 106 ismounted on the container 194 slanted in vertical direction, the drainageof ink can be improved.

A gap, which is filled with ink, is formed between the actuator 106 andthe wave preventing wall 1192 v. The gap between the wave preventingwall 1192 v and the actuator 106 does not hold ink by capillary force.When the container 194 is rolled, ink wave is generated inside thecontainer 194 by the waving, and there is possibility that the actuator106 malfunctions by detecting gas or an air bubble caused by the shockof the ink wave. By providing the wave preventing wall 1192 v, ink wavearound the actuator 106 can be prevented so that the malfunction of theactuator 106 can be prevented.

The actuator 106 of the ink cartridge 180B shown in FIG. 45(B) ismounted on the side wall of the supply port of the container 194. Theactuator 106 can be mounted on the side wall or bottom face of thecontainer 194 if the actuator 106 is mounted nearby the ink supply port187. The wave preventing wall 1192W is provided nearby the ink supplyport 187 inside the container 194 such that the wave preventing wall1192W faces to the actuator 106. The wave preventing wall 1192 w isformed in L-shape to effectively prevent the wave of ink. Moreover, theactuator 106 is preferably mounted on the center of the width directionof the container 194. Because ink is supplied to the outside through theink supply port 187, ink and actuator 106 reliably contacts until thetiming of the ink near end by providing the actuator 106 nearby the inksupply port 187. Therefore, the actuator 106 can reliably detect thetiming of the ink near end.

Furthermore, by providing the actuator 106 nearby the ink supply port187, the setting position of the actuator 106 to the connection point onthe carriage on the ink container becomes reliable during the mountingof the ink container on the cartridge holder of the carriage. It isbecause the reliability of coupling between the ink supply port with theink supply needle is most important during the coupling of the inkcontainer and the carriage. If there is even a small gap, the tip of theink supply needle will be hurt or a sealing structure such as O-ringwill be damaged so that the ink will be leaked. To prevent this kind ofproblems, the ink jet printer usually has a special structure that canaccurately positioning the ink container during the mounting of the inkcontainer on the carriage. Therefore, the positioning of the actuator106 becomes reliable by arranging the actuator nearby the ink supplyport. Furthermore, the actuator 106 can be further reliably positionedby mounting the actuator 106 at the center of the width direction of thecontainer 194. It is because the waving is the smallest when the inkcontainer rolls along an axis, the center of which is center line of thewidth direction, during the mounting of the ink container on the holder.

FIG. 46 shows further other embodiment of the ink cartridge 180. FIG.46(A) shows a cross section of an ink cartridge 180C, and FIG. 46(B)shows a cross section which enlarges the side wall 194 b of an inkcartridge 180C shown in FIG. 46(A). FIG. 46(C) shows perspective viewfrom the front of the side wall 194 b of the ink cartridge 180C. Thesemiconductor memory device 7 and the actuator 106 are formed on thesame circuit board 610 in the ink cartridge 180C. As shown in FIG. 46(A)the wave preventing wall 1192 x is provided inside the container 194such that the wave preventing wall 1192 x faces to the actuator 700. Asshown in FIG. 46(B) and (C), the semiconductor memory device 7 is formedon the upper side of the circuit board 610, and the actuator 106 isformed on the lower side of the semiconductor memory device 7 on thesame circuit board 610. A different-type O-ring 614 is mounted on theside wall 194 b such that the different-type O-ring 614 surrounds theactuator 106. A plurality of caulking part 616 is formed on the sidewall 194 b to couple the circuit board 610 with the container 194. Bycoupling the circuit board 610 with the container 194 using the caulkingpart 616 and pushing the different-type O-ring 614 to the circuit board610, the vibrating region of the actuator 106 can contacts with ink, andat the same time, the inside of the ink cartridge is sealed from outsideof the ink cartridge.

A terminals 612 are formed on the semiconductor memory device 7 andaround the semiconductor memory device 7. The terminal 612 transfer thesignal between the semiconductor memory device 7 and outside the ink jetrecording apparatus. The semiconductor memory device 7 can beconstituted by the semiconductor memory which can be rewritten such asEEPROM. Because the semiconductor memory device 7 and the actuator 106are formed on the same circuit board 610, the mounting process can befinished at one time during mounting the semiconductor memory device 7and the actuator 106 on the ink cartridge 180C. Moreover, the workingprocess during the manufacturing of the ink cartridge 180C and therecycling of the ink cartridge 180C can be simplified. Furthermore, themanufacturing cost of the ink cartridge 180C can be reduced because thenumbers of the parts can be reduced.

The actuator 106 detects the ink consumption status inside the container194. The semiconductor memory device 7 stores the information of inksuch as residual quantity of ink detected by the actuator 106. That is,the semiconductor memory device 7 stores the information related to thecharacteristic parameter such as the characteristic of ink and the inkcartridge used for the actuator 106 when detecting the ink consumptionstatus. The semiconductor memory device 7 previously stores the resonantfrequency of when ink inside the container 194 is full, that is, whenink is filled in the container 194 sufficiently, or when ink in thecontainer 194 is end, that is, ink in the container 194 is consumed, asone of the characteristic parameter. The resonant frequency when the inkinside the container 194 is full status or end status can be stored whenthe ink container is mounted on the ink jet recording apparatus for thefirst time. Moreover, the resonant frequency when the ink inside thecontainer 194 is full status or end status can be stored during themanufacturing of the container 194. Because the unevenness of thedetection of the residual quantity of ink can be compensated by storingthe resonant frequency when the ink inside the container 194 is fullstatus or end status in the semiconductor memory device 7 previously andreading out the data of the resonant frequency at the ink jet recordingapparatus side, it can be accurately detected that the residual quantityof ink is decreased to the reference value.

FIG. 47 shows further other embodiment of the ink cartridge 180. The inkcartridge 180E shown in FIG. 47(A) mounts a actuator 606 which is longin vertical direction on the side wall 194 b of the container 194. Thewave preventing wall 1192 x is provided inside the container 194 suchthat the wave preventing wall 1192 x faces to the whole of the vibratingregion of the actuator 106. The change of the residual quantity of inkinside the container 194 can be detected continuously by the actuator606 which is long in vertical direction. The length of the actuator 606is preferably longer than the half of the height of the side wall 194 b.In FIG. 47(A), the actuator 606 has the length from the substantiallyfrom the top end to the bottom end of the side wall 194 b. Therefore,the wave preventing wall 1192 x also has a length substantially from thetop end to the bottom end of the side wall 194 b. By providing the wavepreventing wall 1192 x, the wave preventing wall 1192 x prevents thewave of ink around the actuator 606 and prevents the malefaction of theactuator 606. Furthermore, the wave preventing wall 1192 x prevents thebubble generated by the waving of ink to enter to the actuator 606.

The ink cartridge 180F shown in FIG. 47(B) mounts a plurality ofactuators 106 on the side wall 194 b of the container 194 and comprisesa wave preventing wall 1192 x on the face of the plurality of actuators606. The ink cartridge 180F further comprises the wave preventing wall1192 x, which is long in vertical direction, along the side wall 194 bwith predetermined gap with the side wall 194 b inside the container194. A gap which is filled with ink is formed between the actuator 106and the wave preventing wall 1192 x. Moreover, the gap between the wavepreventing wall 1192 x and the actuator 106 has a enough distance suchthat the gap does not hold ink by capillary force. When the container194 is rolled, ink wave is generated inside the container 194 by thewaving, and there is possibility that the actuator 106 malfunctions bydetecting gas or an air bubble caused by the shock of the ink wave. Assimilar to the embodiment shown in FIG. 47(B), by providing the wavepreventing wall 1192 x, ink wave around the actuator 106 can beprevented so that the malfunction of the actuator 106 can be prevented.The wave preventing wall 1192 x also prevents the air bubble generatedby the waving of ink to enter to the actuator 106.

FIG. 48 shows further other embodiment of the ink cartridge 180. The inkcartridge 180G shown in FIG. 48(A) has a top wall 1080 and a bottom wall1090, each of which is located on the upside and downside of the inksurface inside the container 194. A plurality of wave preventing walls212 a are extended from the top wall 1080 downward to the bottom wall1090. Because each of lower end of the partition walls 212 and thebottom face of the container 194 has a predetermined gap, the bottompart of the container 194 communicates with each other. The inkcartridge 180G has a plurality of containing chambers 213 divided by theeach of plurality of partition walls 212. The bottom part of theplurality of the containing chambers 213 communicates with each other.The actuator 106 is mounted on the side wall 1070 which faces to the inksupply port 187. The actuator 106 is arranged on substantially center ofthe top face 194 c of the containing chamber 213 of the container 194.The volume of the containing chamber 213 is arranged such that thevolume of the containing chamber 213 of the ink supply port 187 is thelargest, and the volume of the containing chamber 213 graduallydecreases as the distance from the ink supply port 187 increases to theinner part of the ink cartridge 180G. Therefore, the containing chamber213 becomes wider towards from the actuator 106 mounting side of thecontaining chamber 213 to the ink supply port 187 side of the containingchamber 213.

Because ink is drained from the ink supply port 187, and air enters fromthe air introducing inlet 185, ink is consumed from the containingchamber 213 of the ink supply port 187 side to the containing chamber213 of the inner part of the ink cartridge 180G. For example, the ink inthe containing chamber 213 which is most near to the ink supply port 187is consumed, and during the ink level of the containing chamber 213which is most near to the ink supply port 187 decreases, the othercontaining chamber 213 are filled with ink. When the ink in thecontaining chamber 213 which is most near to the ink supply port 187 isconsumed totally, air enters to the containing chamber 213 which issecond by counted from the ink supply port 187, then the ink in thesecond containing chamber 213 is beginning to be consumed so that theink level of the second containing chamber 213 begin to decrease. Atthis time, ink is filled in the containing chamber 213 which is third ormore than third by counted from the ink supply port 187. In this way,ink is consumed from the containing chamber 213 which is most near tothe ink supply port 187 to the containing chamber 213 which is far fromthe ink supply port 187 in order.

As shown above, because the actuator 106 is arranged on the containingchamber 213 that is farthermost from the ink supply port 187, theactuator 106 can detect the ink end. Furthermore, the plurality of wavepreventing walls 212 a can effectively prevent the waves of ink.

The ink cartridge 180H shown in FIG. 48(B) has a top wall 1080 and abottom wall 1090, each of which is located on the upside and downside ofthe ink surface inside the container 194. A plurality of wave preventingwalls 212 b are extended from the top wall 1080 and the bottom wall 1090alternately. There are gap between the partition wall 212 b, whichextends from the bottom wall 1090, among the plurality of the wavepreventing wall 212 b and the side wall, not shown in the figure,located on width direction of the container 194. Therefore, the level ofink surface in each containing chamber 213 is equal.

Furthermore, among the plurality of wave preventing wall 212 b, the wavepreventing wall 212 b which extends from the top wall 1090 and the sidewall, not shown in the figure, located on width direction of thecontainer 194 can be coupled liquid-tightly or air-tightly. In case thewave preventing wall 212 b which is nearest to the actuator 106 amongthe plurality of wave preventing wall 212 b extends from the top wall1080, gas enters to the containing chamber 213 which is nearest to theactuator 106 when the level of ink surface inside the container 194reaches to the lower end of the wave preventing wall 212 b which isnearest to the actuator 106. Therefore, the level of ink surface fordetecting the ink end is determined by the position of the lower end 212f to the level of ink surface along a vertical direction

In the ink cartridge 180I shown in FIG. 48(C), the actuator 106 ismounted on the side wall 1070 around the boundary of the side wall 1070and the top wall 1080. The ink cartridge 180I includes at least twocontaining chambers of containing chamber 213 a and containing chamber213 b which are partitioned by the wave preventing wall 212 c. Among twocontaining chambers, a negative pressure generating member 1100 whichgenerates a negative pressure is provided on the supply port sidecontaining chamber 213 a which is relatively near to the ink supply port187. Among two containing chambers, the actuator 106 is provided on theinner side containing chamber 213 b which is relatively far from the inksupply port 187.

A buffer 214 is formed on the top wall 1080 of the containing chamber213 b. The buffer 214 is a concave part which accepts the bubble whichenters into the ink cartridge 180I when the ink cartridge 180I ismanufactured or when the ink cartridge 180I is left for a long periodwithout to be used. In FIG. 48(C), the buffer 214 is formed as a concavepart which overhangs from the side wall 194 b of the container 194.Because the negative pressure generating member 1100 and the buffer 214accepts the bubbles enters inside the containing chamber 213 b, thenegative pressure generating member 1100 and the buffer 214 can preventthe malfunction of the actuator 106 such as detecting the ink end by theattaching of bubbles on the actuator 106. Furthermore, the ink quantitywhich can be consumed after detecting the ink end can be changed bychanging the capacity of containing chamber 213 b and the length of thewave preventing wall 212 c.

In the ink cartridge 180J shown in FIG. 48(D), a plurality of wavepreventing walls 212 d are extended from the side wall 1070 and the sidewall 1110 of the container 194 alternately. Furthermore, each of one end212 dd of each of the wave preventing wall 212 d is sloped toward theupside of ink surface. Moreover, A gap, in a degree which can passthrough ink, is provided between the each of wave preventing walls 212 dand the side wall, not shown in the figure, which intervene between theside wall 1070 of the container 194 and the side wall 1110. Therefore,ink does not remain on the wave preventing wall 212 d. A plurality ofactuators 106 are mounted on the side wall 1070 which extendssubstantially vertically to ink surface among the wall of container 194.A plurality of actuators 106 is mounted on the different height to theink surface with each other. Thereby the actuator 106 can detect the inkconsumption status step by step. In the present embodiment, the buffer214 is provided around the side wall 1070 of the actuator 106 mountingside among the top wall 1080.

FIG. 49 shows a plan cross sectional view of the further anotherembodiment of the ink cartridge according to the present invention. Inthe ink cartridge 180K of the present embodiment, the actuator 106 ismounted on the side wall 1070 which faces to the ink supply port 187.Each of a plurality of wave preventing wall 212 e extends from the firstside wall 1120 a and the second side wall 1120 b, which intervenebetween side wall 1070 and the side face where the ink supply port 187is provided, alternatively. By the plurality of wave preventing wall 212e which extends from the side wall 1120 a and the 1120 b, the actuator106 is effectively protected from the wave of ink and the generation ofthe bubbles is suppressed.

FIG. 50 shows a plan cross sectional view of the further anotherembodiment of the ink cartridge according to the present invention. Inthe ink cartridge 180L of the present embodiment, the actuator 106 ismounted on the side wall 1070 which faces to the ink supply port 187.The wave preventing wall 212 g includes a bending part 800, at least apart of the end of the wave preventing wall of which is bent toward theside wall 1070 where the actuator 106 is mounted. A capillary force doesnot work between the wave preventing wall 212 g and the actuator 106.Furthermore, a gap, on which a capillary force works, is providedbetween the bending part 800 and the side wall 1070. Therefore, theentering of the bubbles between the actuator 106 and the wave preventingwall 212 g can be prevented. The ink level around the actuator 106 isequal to the other ink level in the ink cartridge 180L. Therefore, theactuator 106 can accurately detect the ink consumption status inside theink cartridge 180L.

FIG. 51 shows other embodiment of the ink cartridge using the actuator106. The ink cartridge 220A shown in FIG. 51(A) has a first wavepreventing wall 222 provided such that it extends from the top wall1081, which locates upside of the ink surface, downward to the inksurface among the wall of the ink cartridge 220A. Because there is apredetermined gap between the lower end of the first wave preventingwall 222 and the bottom wall 1091 of the ink cartridge 220A, ink canflows into the ink supply port 230 through the bottom face of the inkcartridge 220A. A second wave preventing wall 224 is formed such thatthe second wave preventing wall 224 extends upward from the bottom faceof the ink cartridge 220A on the ink supply port 230 side of the firstwave preventing wall 222. Because there is a predetermined gap betweenthe upper end of the second wave preventing wall 224 and the top face ofthe ink cartridge 220A, ink can flows into the ink supply port 230through the top face of the ink cartridge 220A.

A ventilation side ink chamber 225 a is formed on the inner part of thefirst wave preventing wall 222, seen from the ink supply port 230, bythe first wave preventing wall 222. On the other hand, a detection sideink chamber 225 b is formed on the front side of the second wavepreventing wall 224, seen from the ink supply port 230, by the secondwave preventing wall 224. The volume of the ventilation side ink chamber225 a is larger than the volume of the detection side ink chamber 225 b.A detection side small ink chamber 227 is formed by providing a gap,which can generate the capillary phenomenon, between the first wavepreventing wall 222 and the second wave preventing wall 224. Therefore,the ink in the ventilation side ink chamber 225 a is collected to thedetection side small ink chamber 227 by the capillary force of thedetection side small ink chamber 227. Therefore, the detection sidesmall ink chamber 227 can prevent that the air or air bubble enters intothe detection side ink chamber 225 b. Furthermore, the ink level in thedetection side ink chamber 225 b can decrease steadily and gradually.Because the ventilation side ink chamber 225 a is formed at more innerpart of the detection side ink chamber 225 b, seen from the ink supplyport 230, the ink in the detection side ink chamber 225 b is consumedafter the ink in the ventilation side ink chamber 225 a is consumed.

The actuator 106 is mounted on the side wall 1071 of the ink cartridge220A of the ink supply port 230 side, that is, the side wall 1071 of thedetection side ink chamber 225 b of the ink supply port 230 side. Theactuator 106 detects the ink consumption status inside the detectionside ink chamber 225 b. The residual quantity of ink at the timingclosed to the ink near end can be detected stably by mounting theactuator 106 on the side wall 1071 of the detection side ink chamber 225b. Furthermore, by changing the height of the mounting position of theactuator 106 on the side wall 1071 of the detection side ink chamber 225b, the timing to determine which ink residual quantity as an ink end canbe freely set. Because ink is sullied from the ventilation side inkchamber 225 a to the detection side ink chamber 225 b by the detectionside small ink chamber 227, the actuator 106 does not influenced by thewaving of ink caused by the waving of the ink cartridge 220A, andactuator 106 can thus reliably measure the ink residual quantity.Furthermore, because the detection side small ink chamber 227 holds ink,the detection side small ink chamber 227 can prevent ink to flowbackward from the detection side ink chamber 225 b to the ventilationside ink chamber 225 a.

A check valve 228 is provided on the top face of the ink cartridge 220A.The leaking of ink outside of the ink cartridge 220A caused by thewaving of the ink cartridge 220A can be prevented by the check valve228. Furthermore, the evaporation of ink from the ink cartridge 220A canbe prevented by providing the check valve 228 on the top face of the inkcartridge 220A. If ink in the ink cartridge 220A is consumed, andnegative pressure inside the ink cartridge 220A exceeds the pressure ofthe check valve 228, the check valve 228 opens and introduces air intothe ink cartridge 220A. Then the check valve 228 closes to maintain thepressure inside the ink cartridge 220A to be stable.

FIGS. 51(C) and (D) shows a detailed cross-section of the check valve228. The check valve 228 shown in FIG. 51(C) has a valve 232 whichincludes flange 232 a formed by rubber. An airhole 233, whichcommunicates air between inside and outside of the ink cartridge 220, isprovided on the ink cartridge 220 such that the airhole 233 faces to theflange 232 a. The airhole 233 is opened and closed by the flange 232 a.The check valve 228 opens the flange 232 a inward the ink cartridge 220when the negative pressure in the ink cartridge 220 exceeds the pressureof the check valve 228 by the decrease of ink inside the ink cartridge220A, and thus the air outside the ink cartridge 220 is introduced intothe ink cartridge 220. The check valve 228 shown in FIG. 51(D) has avalve 232 formed by rubber and a spring 235. If the negative pressureinside the ink cartridge 220 exceeds the pressure of the check valve228, the valve 232 presses and opens the spring 235 to introduce theoutside air into the ink cartridge 220 and then closes to maintain thenegative pressure inside the ink cartridge 220 to be stable.

The ink cartridge 220B shown in FIG. 51((B) has a porous member 242 inthe ventilation side ink chamber 225 a instead of providing the checkvalve 228 on the ink cartridge 220A as shown in FIG. 51(A). The porousmember 242 holds the ink inside the ink cartridge 220B and also preventsink to be leaked outside of the ink cartridge 220B during the waving ofthe ink cartridge 220B.

FIG. 52 is a cross sectional view of an embodiment of an ink cartridgefor use with a single color, for example, the black ink as an embodimentof the liquid container according to the present invention. An inkcartridge shown in FIG. 52 is based on the method that detects theposition of the liquid surface or an existence of liquid inside a liquidcontainer by detecting a resonant frequency by measuring the counterelectromotive force generated by the residual vibration remained in thevibrating section among the above mentioned method. The actuator 106 isused for an embodiment of the liquid censor that detects liquid. The inkcartridge of the embodiment shown in FIG. 52 comprises a container 1which contains liquid K and includes top wall 1030 located upside of theliquid surface of ink K, an ink supply port 2 which supplies liquid Koutside the container 1, an actuator 106 which detects ink consumptionstatus inside the container 1, and a first partition wall 193 a whichpartitions at least two ink chamber such that ink K in both of the inkchamber can communicate with each other inside the container 1. At leasttwo ink chambers include a ventilation side ink chamber 123 a whichcommunicate with atmosphere and the detecting side ink chamber 123 b.The actuator 106 is mounted on the top wall 1030 of the ink chamber 123b.

The airhole 233 is provided on the top wall 1030 of the ventilation sideink chamber 123 a which ventilates with atmosphere. The check valve 228shown in FIG. 56 can be used for airhole 233. However, the form of theairhole 233 is not limited to the check valve 228 shown in FIG. 56. Ifink K is consumed and the container 1 inside becomes extremely negativepressure, air is introduced to the ventilation side ink chamber 123 afrom the outside of the container 1 by the airhole 233, and the airhole233 thus prevents the pressure inside the container 1 to be negative.Therefore, with the consumption of ink advanced, air is introduced tothe ventilation side ink chamber 123 a through the airhole 233, and thelevel of liquid surface of ink K decreases.

The partition wall 193 a is coupled with the top wall 1030liquid-tightly. Therefore, even the ink is consumed, ink K is filled inthe detection side ink chamber 123 b in the container 1 until the levelof liquid surface of ink K reaches to the lower end 193 aa of thepartition wall 193 a. When the ink consumption advances and the level ofliquid surface of ink K reaches to the lower end 193 aa of the partitionwall 193 a, gas enters to the detection side ink chamber 123 b. Therebythe ink k remained in the detection side ink chamber 123 b flows out tothe ink supply port 2, and the medium existed around the actuator 106changes from ink K to atmosphere. Therefore, the actuator 106 can detectthat the status inside the ink cartridge is in ink end status. Thus, itis the lower end 193 aa to determine which level of the liquid surfaceof ink K to be a ink end. Furthermore, the volume of the detection sideink chamber 132 b is determined by the width between the side wall 1010,which extends substantially vertical to the ink surface, and thepartition wall 193 a. Therefore, the ink quantity remains inside thecontainer 1 when detecting the ink end can be set by the width betweenthe side wall 1010 and the partition wall 193 a and the height of thelower end 193 aa in the direction vertical to the ink surface.

The volume of the detection side ink chamber 123 b is preferably half orsmaller than half of the volume of the ventilation side ink chamber 123a. A capillary force such as to hold ink K does not work on thedetection side ink chamber 123 b.

The actuator 106 can be used as a means of merely detecting thevibration without vibrating itself. Moreover, the detailed configurationof the airhole will be described in FIG. 56.

A packing ring 4 and a valve body 6 are provided in the ink supply port2. Referring to FIG. 54, the packing ring 4 is engaged with the inksupply needle 32 communicating with a recording head 31, in afluid-tight manner. The valve body 6 is constantly and elasticallycontacted against the packing ring 4 by way of a spring 5. When the inksupply needle 32 is inserted, the valve body 6 is pressed by the inksupply needle 32 so as to open an ink passage, so that ink inside thecontainer 1 is supplied to the recording head 31 via the ink supply port2 and the ink supply needle 32. On an upper wall of the container 1,there is mounted a semiconductor memory means 7 which stores data on inkinside the ink cartridge.

If there is no partition wall 193 a in the container 1, bubbles may begenerated by the waving of ink, which is caused by the vibration of inkcartridge generated by such as the scanning operation during theprinting process. Then, there is a danger that the actuator 106 maydetect mistakenly that there is enough ink in the container 1 if the inkattaches to the actuator 106 by the waving of ink even if there islittle amount of ink in the container 1. Moreover, there is also adanger that the actuator 106 may detect mistakenly that there is no inkif the bubble attaches to the actuator 106 even if the ink is filled inthe container 1.

However, according to the embodiment of the liquid container of thepresent embodiment, the partition wall prevents the waving of ink aroundthe piezoelectric device even when the ink cartridge vibrates by such asthe scanning operation during the printing process. By preventing thewaving of ink around the piezoelectric device, the partition wall 193 aprevents the generation of the bubbles. Furthermore, even the bubblesgenerate in the ventilation side ink chamber, the partition wallseparates the ventilation side ink chamber and the detection side inkchamber air-tightly and liquid-tightly. Therefore, the partition wallprevents the bubbles to move close to the actuator 106 and contact withthe actuator 106.

There is no limitation of the size, thickness, shape, flexibility, andmaterial for the partition wall. Therefore, the size of the partitionwall can be made relatively larger or smaller. The thickness of thepartition wall can be made relatively thicker or thinner. Furthermore,the shape of the partition wall can be square or rectangular. Preferablythe shape, size and thickness of the partition wall is changed accordingto the shape of the ink cartridge. Furthermore, the partition wall canbe made from the hard material or flexible material. For example,material such as plastic, tefron, nylon, polypropylene, or PET can beused for the partition wall. Preferably, the partition wall is made fromthe air-tight or liquid-tight material which does not pass through gasor liquid. Moreover, the container and the partition wall are made fromsame material so that the container and the partition wall can be formedin one body. The manufacturing process of the ink cartridge can therebybe reduced.

FIG. 53 is a perspective view of the ink cartridge which stores pluraltypes of inks, viewed from an outside thereof, according to anembodiment. FIG. 53 is a perspective view from the side of the top wall1038 which is located upside of the liquid surface of ink K among thewall of the container 8. A container 8 is divided into three inkchambers 9, 10 and 11. Ink supply ports 12, 13 and 14 are formed for therespective ink chambers. On a top wall 1038 of the respective inkchambers 9, 10 and 11, the respective actuators 15, 16 and 17 aremounted on the container 8 so that the actuators 15, 16, and 17 cancontact with the ink which is housed in each ink chambers via thethrough hole, not shown in the figure, provided on the container 8.Partition walls, not shown in the figure, is provided each of inside ofthe ink container 9, 10 and 11 as similar to the ink cartridge shown inFIG. 52. The partition walls provided in each of ink chambers 9, 10, and11 separates the each ink chambers 9, 10, and 11 into ventilation sideink chamber and detection side ink chamber.

FIG. 54 is a cross sectional view showing an embodiment of a major partof the ink-jet recording apparatus suitable for the ink cartridge shownin FIG. 52 and FIG. 53. A carriage 30 capable of reciprocating in thedirection of the width of the recording paper is equipped with a subtankunit 33, while the recording head 31 is provided in a lower face of thesubtank unit 33. Moreover, the ink supply needle 32 is provided in anink cartridge mounting face side of the subtank unit 33. In FIG. 54, theink cartridge shown in FIG. 52 and FIG. 53 are used. However, the inkcartridge shown in other figures also can be used.

When the ink supply port 2 of the container 1 is inserted through theink supply needle 32 of the subtank unit 33, the valve body 6 recedesagainst the spring 5, so that an ink passage is formed and the inkinside the container 1 flows into the ink chamber 34. At a stage wherethe ink chamber 34 is filled with ink, a negative pressure is applied toa nozzle opening of the recording head 31 so as to fill the recordinghead with ink. Thereafter, the recording operation is performed.

When the ink is consumed in the recording head 31 by the recordingoperation, a pressure in the downstream of the flexible valve 36decreases. Then, the flexible valve 36 is positioned away from a valvebody 38 so as to become opened. When the flexible valve 36 is opened,the ink in the ink chamber 34 flows into the recording head 31 throughthe ink passage 35. Accompanied by the ink which has flowed into therecording head 31, the ink in the container 1 flows into the subtankunit 33 via the ink supply needle 32.

FIG. 55 is a cross sectional view of an another embodiment of an inkcartridge as an embodiment of the liquid container according to thepresent invention. In an ink cartridge of the present embodiment, a topwall 1039, which locates upside of the liquid surface of ink K, issloped to the liquid surface of ink K. The actuators 106 are mounted onthe top wall 1039 such that the actuator 106 can contacts with inkthrough the through hole 1 c provided on the top wall 1039. Thepartition wall 193 c extends from the top wall 1039 downward to the inksurface. Furthermore, the present embodiment has a second partition wall193 d which extends from the top wall 10398 inside the detection sideink chamber 123 b and separates the detection side ink chamber 123 b atleast into two detection side small ink chambers 1123 a and 1123 b suchthat ink housed in both of the detection side small ink chamber, 1123 aand 1123 b can communicate each other. Each of two actuators 106 a and106 b is mounted on the top wall 1039 of each of the detection sidesmall ink chambers 1123 a and 1123 b, respectively.

The volume of the ventilation side ink chamber 123 a which is close tothe ink supply port 2 is larger than the volume of the detection sideink chamber 123 b which is relatively far from the ink supply port 2.Furthermore, the volume of the detection side small ink chamber 1123 awhich is close to the ink supply port 2 is larger than the volume of thedetection side small ink chamber 1123 b which is relatively far from theink supply port 2 within the detection side ink chamber 123 b.Therefore, ink in the ventilation side ink chamber 123 a is consumed atfirst. With consumption of ink advanced, the level of ink surface in theventilation side ink chamber 123 a decreases. On the other hand, becausethe partition wall 193 cc and the top wall 1039 is coupledliquid-tightly or air-tightly, the detection side ink chamber 123 b isfilled with ink until the level of ink surface reaches to the lower end193 cc of the partition wall 193 c.

Next, if the ink surface in the ventilation side ink chamber 123 areaches to the lower end 193 cc of the partition wall 193 c, ink in thedetection side small ink chamber 1123 a is beginning to be consumedbecause ink in the detection side small ink chamber 1123 a flows out tothe ink supply port 2. With consumption of ink advanced, the level ofink surface in the detection side small ink chamber 1123 a decreases. Onthe other hand, because the partition wall 193 dd and the top wall 1039is coupled liquid-tightly or air-tightly, the detection side small inkchamber 1123 b is filled with ink until the level of ink surface reachesto the lower end 193 dd of the partition wall 193 d. Finally, if thelevel of ink surface of the detection side small ink chamber 1123 areaches to the lower end 193 dd of the partition wall 193 d, ink in thedetection side small ink chamber 1123 b is beginning to be consumedbecause ink in the detection side small ink chamber 1123 b flows out tothe ink supply port 2.

Therefore, the actuators 106 a and 106 b can detect the ink consumptionstatus step by step. Moreover, because the volume of the ink chambersare designed such that the volume decreases from the ventilation sideink chamber 123 a, which is nearest to the ink supply port 2, to thedetection side small ink chamber 1123 a and further to the detectionside small ink chamber 1123 b, which is farthest from the ink supplyport 2, the frequency of detecting an ink by the actuators 106 a and 106b increases with the advance of ink consumption. Therefore, thefrequency of detection of ink increases with the decreasing of residualquantity of ink.

The container of the ink cartridge shown in FIG. 55 has one secondpartition wall. As other embodiment, the container can have a pluralityof partition walls so that the detection side ink chamber 123 b isseparated into three or over detection side small ink chambers. Aplurality of second partition walls separates the detection side inkchamber 123 b into two or over detection side small ink chambers. Eachof the volumes of the of the detection side small ink chambers 1123 bcan be varied gradually from the one side of the side wall to the otherside of side wall which faces each other. Preferably, as shown in FIG.55, each of the volume of the detection side small ink chambersdecreases gradually from the detection side small ink chamber, which isrelatively near to the ink supply port 2, to the detection side smallink chamber, which is relatively far from the ink supply port 2. Then,the actuator 106 can detects the process of gradual consumption of ink Kinside the ink cartridge.

Moreover, because the volume of the ink chambers are designed such thatthe volume decreases from the detection side small ink chamber 1123 a,which is near to the ink supply port 2, to the detection side small inkchamber, which is far from the ink supply port 2, the time interval ofdetecting a decrease of ink by the actuator 106 gradually decreases asthe ink cartridge shown in FIG. 55. Therefore, the frequency ofdetection of ink increases with the decreasing of residual quantity ofink.

Furthermore, the actuator 106 a is mounted nearby the partition wall 193c, and the actuator 106 b is mounted nearby the partition wall 193 d.Therefore, even if the bubble G generates and enters into the detectionside ink chamber 123 b when the ink inside the ventilation side inkchamber 123 a does not reach to the lower end 193 cc of the partitionwall 193 c, the bubble G stays in the upper side of boundary between thetop wall 1039 and the partition wall 193 c or the upper side of boundarybetween the top wall 1039 and the side wall 1030. Therefore, the bubbleG does not attaches to the actuator 106.

FIG. 56 shows further other embodiment of the ink-cartridge using theactuator 106. The ink cartridge 220A shown in FIG. 56(A) has a firstpartition wall 222 provided such that it extends downward from the topface of the ink cartridge 220A. Because there is a predetermined spacebetween the lower end of the first partition wall 222 and the bottomface of the ink cartridge 220A, ink can flows into the ink supply port230 through the bottom face of the ink cartridge 220A. A secondpartition wall 224 is formed such that the second partition wall 224extends upward from the bottom face of the ink cartridge 220A on themore ink supply port 230 side of the first partition wall 222. Becausethere is a predetermined space between the upper end of the secondpartition wall 224 and the top face of the ink cartridge 220A, ink canflows into the ink supply port 230 through the top face of the inkcartridge 220A.

A ventilation side ink chamber 225 a is formed relatively near to theairhole 233. On the other hand, a detection side ink chamber 225 b isformed relatively far from the airhole 233. By the second partition wall224, the detection side ink chamber 225 b and a detection side small inkchamber 227 are formed. The volume of the ventilation side ink chamber225 a is larger than the volume of the detection side ink chamber 225 b.A detection side small ink chamber 227 is formed by providing a gap,which can generate the capillary phenomenon, between the first partitionwall 222 and the second partition wall 224. Therefore, the ink in theventilation side ink chamber 225 a is collected to the detection sidesmall ink chamber 227 by the capillary force of the detection side smallink chamber 227. The first partition wall 222 can prevent that the gasor air bubble to enter into the detection side ink chamber 225 b.Furthermore, the ink level in the detection side ink chamber 225 b candecrease steadily and gradually. Because the ventilation side inkchamber 225 a is formed at more inner part of the detection side inkchamber 225 b, seen from the ink supply port 230, the ink in thedetection side ink chamber 225 b is consumed after the ink in theventilation side ink chamber 225 a is consumed.

Because ink is supplied from the ventilation side ink chamber 225 a tothe detection side ink chamber 225 b by the detection side small inkchamber 227, the actuator 106 does not influenced by the rolling of inkcaused by the rolling of the ink cartridge 220A, and actuator 106 canthus reliably measure the ink residual quantity. Furthermore, becausethe detection side small ink chamber 227 holds ink, the detection sidesmall ink chamber 227 can prevent ink to flow backward from thedetection side ink chamber 225 b to the ventilation side ink chamber 225a.

The actuator 106 is mounted on the top wall 1013 of the ink supply port230 side of the detection side ink chamber 225 b. The actuator 106detects the ink consumption status inside the detection side ink chamber225 b. The residual quantity of ink at the timing closed to the ink nearend can be detected stably by mounting the actuator 106 on the side wallof the detection side ink chamber 225 b.

A airhole 233 is provided on the top wall 1013 of the ink cartridge220A. Moreover, a check valve 228 is provided on the airhole 233. Theleaking of ink outside the ink cartridge 220A caused by the rolling ofthe ink cartridge 220A can be prevented by the check valve 228.Furthermore, the evaporation of ink from the airhole 233 of the inkcartridge 220A can be prevented by providing the check valve 228 on thetop face of the ink cartridge 220A. If ink in the ink cartridge 220A isconsumed, and negative pressure inside the ink cartridge 220A exceedsthe pressure of the check valve 228, the check valve 228 opens andintroduces air into the ink cartridge 220A. Then the check valve 228closes to accelerate the drainage of ink from the ink cartridge 220A.

FIG. 57 shows further another embodiment of the ink cartridge using theactuator 106. An ink cartridge 180A shown in FIG. 57 has a partitionwall 212 a which extends downward from the top face 194 c of the inkcontainer 194. The container 194 is separated into a ventilation sideink chamber 213 a and a detection side ink chamber 213 b by thepartition wall 212 a. Because lower end 212 aa of the partition wall 212a and the bottom wall 1 a of the container 194 have a predeterminedspace, the ventilation side ink chamber 213 a and the detection side inkchamber 213 b communicates with each other. The actuator 106 is mountedon the top wall 194 c of the detection side ink chamber 213 b. Thevolume of the detection side ink chamber 213 b is smaller than thevolume of the ventilation side ink chamber 213 a. The volume of thedetection side ink chamber 213 b is preferably smaller than the half ofthe volume of the ventilation side ink chamber 213 a.

A buffer 214 a, that is a concave part for accepting the air bubblewhich enters to the ink cartridge 180A is formed on the top wall 194 cof the detection side ink chamber 213 b. In FIG. 57, the buffer 214 a isformed as a concave part overhang upward from the top wall 194 c of thecontainer 194. The buffer 214 a accepts the air bubble which enters intothe detection side ink chamber 213 b mistakenly when the ink is filledin the detection side ink chamber 213 b. The buffer 214 a therebyprevents the bubbles to attach to the actuator 106. Therefore, thebuffer 214 b prevents the malfunction of the actuator 106 to detect theink end wrongly by the attaching of air bubble to the actuator 106.Furthermore, by adjusting the volume of the detection side ink chamber213 b by changing the length of the partition wall 212 a or changing thewidth between the partition wall 212 a and the side wall 194 b, thepredetermined ink quantity remained after the detection of the ink endcan be changed.

FIG. 58 shows further another embodiment of the ink cartridge 180. Anink cartridge 180B shown in FIG. 58 has a partition wall 212 b which isformed in L-shape. The partition wall 212 f extends from a top wall 194c. A lower end 212 bb of the partition wall 212 b is longer than thelower end 212 aa of the partition wall 212 a in the embodiment shown inFIG. 57. Therefore, gas existed in the ventilation side ink chamber 213a is difficult to enter into the detection side ink chamber 213 b.Therefore, the malfunction of the actuator 106 to detects the ink endwrongly caused by the attaching of bubble to the actuator 106 can befurther prevented. Furthermore, a gap is provided between the lower end212 bb and the bottom wall 1 a. A capillary force, which can hold ink,does not work on the gap provided between the lower end 212 bb and thebottom wall 1 a.

FIG. 59 shows further another embodiment of the ink cartridge 180. Anink cartridge 180C shown in FIG. 59 has a partition wall 212 c which issloped toward the ink surface. The partition wall 212 c extends from atop wall 194 c. The distance between the side wall 194 b of the inkcartridge 180C and the partition wall 212 c narrows toward downside.Therefore, gas existed in the ventilation side ink chamber 213 a isdifficult to enter into the detection side ink chamber 213 b. Therefore,the malfunction caused by the attaching of bubble to the actuator 106can be further prevented. Furthermore, a gap is provided between thelower end 212 cc and the bottom wall 1 a of the container 194. Acapillary force, which can hold ink, does not work on the gap providedbetween the lower end 212 cc of the partition wall 212 c and the sidewall 194 b.

FIG. 60 shows further another embodiment of the ink cartridge 180. Anink cartridge 180D shown in FIG. 60 has a first partition wall 212 dwhich extends downward from the top face 194 c of the ink container 194.Furthermore, a second wall extends from the first partition wall 212 dtoward the side wall 194 b substantially parallel to the ink surface.The container 194 is separated into a ventilation side ink chamber 213 aand a detection side ink chamber 213 b by the first partition wall 212d. Furthermore, the second partition wall 212 e separates the detectionside ink chamber into a first detection side ink chamber 213 c and asecond detection side ink chamber 213 d. A gap is provided between thebottom wall 1 a and the first partition wall 212 d. Furthermore, a gapis provided between the side wall 194 b and the one end 212 ee of thesecond partition wall 212 e. A concave part is provided on a part of topwall 194 c to form a buffer 214 a which accepts the bubble.

One end of the second partition wall 212 e, which extends from thepartition wall 212 d toward the side wall 194 b, extends until to theposition where just under the buffer 214 b. Therefore, first, the firstpartition wall 212 d prevents the entering of bubble into the firstdetection side ink chamber 213 c. If the bubble enters into thedetection side ink chamber 213 c mistakenly, the bubble is introduced tothe position which is just under the buffer 214 a by the secondpartition wall 212 e. Therefore, the bubble is caught by the buffer 214a. Therefore, the malfunction of the actuator 106 to detects the ink endwrongly by the attaching of bubble to the actuator 106, which isprovided in the second detection side ink chamber 213 d, can be furtherprevented.

FIG. 61 shows further another embodiment of the ink cartridge 180. Anink cartridge 180E shown in FIG. 61 has a partition wall 212 a as sameas the partition wall 212 a of FIG. 57. The partition wall 212 a extendsdownward from the top face 194 c of the ink container 194. The container194 is separated into a ventilation side ink chamber 213 a and adetection side ink chamber 213 b by the partition wall 212 a. A gap isprovided between the bottom wall 1 a and the partition wall 212 a.Furthermore, a concave part is provided on a part of top wall 194 c toform a buffer 214 b which accepts the bubble. A tapered face 1040 isprovided between the buffer 214 b and the actuator 106.

Therefore, first, the partition wall 212 a prevents the entering ofbubble into the detection side ink chamber 213 b. If the bubble entersinto the detection side ink chamber 213 b mistakenly, the bubble isdirectly caught by the buffer 214 a or introduced to the buffer 214 balong the tapered face 1040. Therefore, the malfunction of the actuator106 to detects the ink end wrongly by the attaching of bubble to theactuator 106 can be further prevented. The shape and size of the buffercan be other arbitrary shape and size.

FIG. 62 shows further another embodiment of the ink cartridge 180. Anink cartridge 180F shown in FIG. 62 has a protruding part 214 f, whichprotrudes inside the container 194, on a part of the top wall 194 c. Theactuator 106 is mounted on the bottom part of the protruding part 214 f.A partition wall 212 f extends downward from the top face 194 c. Abuffer 214 c is provided for each of the position between the actuator106 and the partition wall 212 f and between the actuator 106 and theside wall 194 b. Therefore, the periphery of the actuator 106 issurrounded by the buffer 214 c.

FIG. 63 shows further another embodiment of the ink cartridge 180. Anink cartridge 180G shown in FIG. 63 has a partition wall 212 extendsdownward from the top face 194 c. The container 194 is separated into aventilation side ink chamber 213 a and a detection side ink chamber 213b by the partition wall 212 g. Uneven part is provided on the top wall194 c, and two actuators 106 are mounted on the protruding part whichprotrudes inside the detection side ink chamber 213 b. The concave partof the top wall 194 c works as a buffer 214 c which accepts bubble.

FIG. 64 shows further other embodiment of the ink cartridge 180. The inkcartridge 1801 shown in FIG. 64 has a plurality of partition walls 212h, 212 i, 212 j, and 212 k, each of which extends downward from the topface 194 c of the ink container 194. The partition wall 212 h is firstpartition wall, and the partition walls 212 i, 212 j, and 212 k are thesecond partition walls. Because each of lower ends 212 hh, 212 ii, 212jj, and 212 kk of each of the partition walls 212 h, 212 i, 212 j, and212 k and the bottom wall 1 a of the container 194 have a predeterminedgap, the bottom part of the container 194 communicates with each other.The ink cartridge 180I has a ventilation side ink chamber 213 a and aplurality of detection side small ink chambers 213 h, 213 i, 213 j, and213 k separated by the each of plurality of partition walls 212 h, 212i, 212 j and 212 k. The bottom part of the ventilation side ink chamber213 a and a plurality of the detection side small ink chambers 213 h,213 i, 213 j, and 213 k communicates with each other. Each of theactuators 106 h, 106 i, 106 j, and 106 k is mounted on the top face 194c of each of the plurality of the detection side small ink chambers 213h, 213 i, 213 j, and 213 k, respectively. Each of the actuators 106 h,106 i, 106 j, and 106 k is arranged on substantially center of the topface 194 c of each of the plurality of the detection side small inkchambers 213 h, 213 i, 213 j, and 213 k, respectively. The volume of theink chamber is arranged such that the volume of the ventilation side inkchamber 213 a which locates ink supply port 187 side is the largest.Moreover, the volume of the ink chamber gradually decreases as thedistance from the ink supply port 187 increases. Therefore, the volumeof the detection side small ink chamber 213 k which is farthest from theink supply port 187 is the smallest among the volume of the inkchambers.

Because gas is introduced from the airhole 233, ink is consumed from theventilation side ink chamber 213 a of the ink supply port 187 side tothe detection side ink chamber 213 k. For example, the ink in theventilation side ink chamber 213 a which is nearest to the ink supplyport 187 is consumed, and during the ink level of the ventilation sideink chamber 213 a decreases, the other detection side small ink chambersare filled with ink. When the ink level in the ventilation side inkchamber 213 a reaches to the lower end 212 hh of the partition wall 212h, air enters into the detection side small ink chamber 213 h, and thenthe ink in the detection side small ink chamber 213 h is beginning to beconsumed. At this time, ink is filled in the detection side small inkchamber 213 i, 213 j, and 213 k. Furthermore, if the ink level in thedetection side small ink chamber 213 h reaches to the lower end 212 iiof the partition wall 212 i, air enters into the detection side smallink chamber 213 i, and then the ink in the detection side small inkchamber 213 i is beginning to be consumed. In this way, ink issequentially consumed from the ventilation side ink chamber 213 a to thedetection side small ink chamber 213 k.

Each of the actuators 106 h, 106 i, 106 j, and 106 k is mounted on thetop wall 194 c of each of the detection side small ink chambers.Therefore, the actuators 106 h, 106 i, 106 j, and 106 k can detect thedecrease of the ink quantity step by step. Furthermore, the volume ofthe ink chambers decreases from the ventilation side ink chamber 213 a,which is near to the ink supply port 187, to the detection side smallink chamber 213 k gradually. Therefore, the time interval of detectingthe decrease of the ink quantity gradually decreases. Therefore, thefrequency of the ink quantity detection can be increased as the ink endis drawing near.

FIG. 65 shows further other embodiment of the ink cartridge 180. FIG. 65shows a cross section of an ink cartridge 180J. The semiconductor memorydevice 7 and the actuator 106 are formed on the same circuit board 610in the ink cartridge 180J.

The semiconductor memory device 7 can be constituted by thesemiconductor memory which can be rewritten such as EEPROM. Because thesemiconductor memory device 7 and the actuator 106 are formed on thesame circuit board 610, the mounting process can be finished at one timeduring mounting the semiconductor memory device 7 and the actuator 106on the ink cartridge 180C. Moreover, the working process during themanufacturing of the ink cartridge 180C and the recycling of the inkcartridge 180C can be simplified. Furthermore, the manufacturing cost ofthe ink cartridge 180C can be reduced because the numbers of the partscan be reduced. Furthermore, a partition wall 212J extends from the topwall 194 c downward to the ink surface. The partition wall 212J preventsthe waving of ink or bubbling. The partition wall 212J thereby preventsthe malfunction of the actuator 106.

The actuator 106 detects the ink consumption status inside the container194. The semiconductor memory device 7 stores the information of inksuch as residual quantity of ink detected by the actuator 106. That is,the semiconductor memory device 7 stores the information related to thecharacteristic parameter such as the characteristic of ink and the inkcartridge used for the actuator 106 when detecting the ink consumptionstatus. The semiconductor memory device 7 previously stores the resonantfrequency of when ink inside the container 194 is full, that is, whenink is filled in the container 194 sufficiently, or when ink in thecontainer 194 is end, that is, ink in the container 194 is consumed, asone of the characteristic parameter. The resonant frequency when the inkinside the container 194 is full status or end status can be stored whenthe ink container is mounted on the ink jet recording apparatus for thefirst time. Moreover, the resonant frequency when the ink inside thecontainer 194 is full status or end status can be stored during themanufacturing of the container 194. Because the unevenness of thedetection of the residual quantity of ink can be compensated by storingthe resonant frequency when the ink inside the container 194 is fullstatus or end status in the semiconductor memory device 7 previously andreading out the data of the resonant frequency at the ink jet recordingapparatus side, it can be accurately detected that the residual quantityof ink is decreased to the reference value.

FIG. 66 shows further other embodiment of the ink cartridge 180. The inkcartridge 180K shown in FIG. 66 has a plurality of partition walls 212m, 212 n, 212 p, and 212 q, each of which extends downward from the topface 194 c of the ink container 194. The partition wall 212 m is thefirst partition wall, and the partition walls 212 n, 212 p, and 212 qare the second partition walls. Because each of lower ends 212 mm, 212nn, 212 pp, and 212 qq of the partition walls 212 m, 212 n, 212 p, and212 q, respectively, and the bottom wall of the container 194 has apredetermined gap, the bottom part of the container 194 communicateswith each other. Moreover, the length of the partition walls 212 m, 212n, 212 p, and 212 q increases from the side near to the airhole 233 inorder. Therefore, each of the gap between the lower ends 212 mm, 212 nn,212 pp, and 212 qq and the bottom wall 1 a narrows in the order of 212m, 212 n, 212 p, and 212 q, sequentially.

Furthermore, the ink cartridge 180K has a ventilation side ink chamber213 a and a plurality of detection side small ink chamber 213 m, 213 n,213 p, and 213 q separated by the each of plurality of partition walls212 m, 212 n, 212 p and 212 q. The bottom part of the ventilation sideink chamber 213 a and a plurality of the detection side small inkchambers 213 m, 213 n, 213 p, and 213 q communicates with each other.Each of the actuators 106 m, 106 n, 106 p, and 106 q is mounted on thetop face 194 c of each of the plurality of the detection side small inkchambers 213 m, 213 n, 213 p, and 213 q, respectively. Each of theactuators 106 m, 106 n, 106 p, and 106 q is arranged on substantiallycenter of the top face 194 c of each of the plurality of the detectionside small ink chambers 213 m, 213 n, 213 p, and 213 q, respectively.

If ink is consumed, gas is introduced from the airhole 233. Therefore,ink is consumed from the ventilation side ink chamber 213 a which isnear to the airhole 233 to the detection side ink chamber 213 q. Forexample, the ink in the ventilation side ink chamber 213 a which isnearest to the airhole 233 is consumed, and during the ink level of theventilation side ink chamber 213 a decreases, the other detection sidesmall ink chambers are filled with ink. When the ink level in theventilation side ink chamber 213 a reaches to the lower end 212 mm ofthe partition wall 212 m, air enters into the detection side small inkchamber 213 m, and then the ink in the detection side small ink chamber213 m is beginning to be consumed. At this time, ink is filled in thedetection side small ink chamber 213 n, 213 p, and 213 q. Furthermore,if the ink level in the detection side small ink chamber 213 m reachesto the lower end 212 nn of the partition wall 212 n, air enters into thedetection side small ink chamber 213 n, and then the ink in thedetection side small ink chamber 213 n is beginning to be consumed. Inthis way, ink is sequentially consumed from the ventilation side inkchamber 213 a to the detection side small ink chamber 213 q.

Because the gap between the each of the lower ends and the bottom wall 1a narrows gradually in the order from the lower ends 212 mm, 212 nn, 212pp, and 212 qq, ink is consumed in the order from the ventilation sideink chamber 213 a, detection side small ink chamber 212 m, 212 n, 212 p,and 212 q, sequentially. Therefore, the gas is difficult to entermistakenly into the ink chambers in the same order mentioned above. Forexample, even if gas enters into the detection side small ink chamber213 m and 213 n mistakenly, and the actuator 106 detects the ink endmistakenly, the partition walls 212 p and 212 q, which is longer thanthe partition walls 212 m and 212 n, prevents the gas to enter into thedetection side small ink chamber 213 p and 213 q. Therefore, theactuators 106 p and 106 q do not mistakenly detect the ink end. Thus, inthe present embodiment, the actuator 106 q detects the ink end finallyand most reliably.

Furthermore, because the partition walls 212 m, 212 n, 212 p, and 212 qprevent the waving of ink, the partition walls 212 m, 212 n, 212 p, and212 q also prevent the generation of the bubble.

Moreover, the intervals between each of the partition walls 212 m, 212n, 212 p, and 212 q with each other can be equal, and the intervalbetween the partition wall 212 q and the side wall 194 b of thecontainer 1 can be equal. In this case, the capacity of each of thedetection side small ink chambers 213 m, 213 n, 213 p, and 213 q can beadjusted by adjusting the length of the partition walls 212 m, 212 n,212 p, and 212 q.

FIG. 67 shows an embodiment around a recording head of part of the inkcartridge and an ink jet recording apparatus which uses the actuator106. In the present embodiment, the ink cartridge 180A shown in FIG. 57is used. However, the ink cartridge in any of the ink cartridge shown inFIG. 58 to FIG. 64 also can be used. Furthermore, the ink cartridge ofthe other form also can be used. A plurality of ink cartridges 180A ismounted on the ink jet recording apparatus which has a plurality of inkintroducing members 182 and a holder 184 each corresponding to the eachof ink cartridge 180, respectively. Each of the plurality of inkcartridges 180A contains different types of ink, for example, differentcolor of ink. The actuator 106, which detects at least acousticimpedance, is mounted on the each of top wall of the plurality of inkcartridge 180A. The actuator 106 and a partition wall 212 a are providedfor each top wall of the plurality of ink cartridge 180A. The residualquantity of ink in the ink cartridge 180 can be detected by mounting theactuator 106 on the ink cartridge 180. The partition wall 212 a prevent&the waving and bubbling of ink.

FIG. 68 shows a detail around the head member of the ink jet recordingapparatus. In the present embodiment, the ink cartridge 180A shown inFIG. 57 is used. However, the ink cartridge in any of the ink cartridgeshown in FIG. 58 to FIG. 64 also can be used. Furthermore, the inkcartridge of the other form also can be used. The ink jet recordingapparatus has an ink introducing member 182, a holder 184, a head plate186, and a nozzle plate 188. A plurality of nozzle 190, which jet outink, is formed on the nozzle plate 188. The ink introducing member 182has an air supply hole 181 and an ink introducing inlet 183. The airsupply hole 181 supplies air to the ink cartridge 180. The inkintroducing inlet 183 introduces ink from the ink cartridge 180A. Theink cartridge 180A has an air introducing inlet 185 and an ink supplyport 187. The air introducing inlet 185 introduces air from the airsupply hole 181 of the ink introducing member 182. The ink supply port187 supplies ink to the ink introducing inlet 183 of the ink introducingmember 182. By introducing air from the ink introducing member 182 tothe ink cartridge 180, the ink cartridge 180 accelerates the supply ofink from the ink cartridge 180A to the ink introducing member 182. Theholder 184 communicates ink, which is supplied from the ink cartridge180A through the ink introducing member 182, to the head plate 186. Inkis supplied to the head from the ink cartridge 180A through the inkintroducing member 182 and discharged to the recording medium fromnozzle. In this way, the ink jet recording apparatus performs theprinting on the recording medium.

FIG. 69 is a cross sectional view of an embodiment of an ink cartridgefor use with a single color, for example, the black ink as an embodimentof the liquid container according to the present invention. An inkcartridge shown in FIG. 69 is based on the method that detects theposition of the liquid surface or an existence of liquid inside a liquidcontainer by detecting a resonant frequency by measuring the counterelectromotive force generated by the residual vibration remained in thevibrating section among the above mentioned method. The actuator 106 isused for an embodiment of the liquid censor that detects liquid. The inkcartridge of the embodiment shown in FIG. 69 comprises a container 1which contains liquid K and includes top wall 1030 located upside of theliquid surface of ink K, an ink supply port 2 which supplies liquid Koutside the container 1, an actuator 106 which detects ink consumptionstatus inside the container 1, and a first partition wall 193 a whichpartitions at least two ink chamber such that ink K in both of the inkchamber can communicate with each other inside the container 1.

At least two ink chambers include a ventilation side ink chamber 123 awhich communicate with atmosphere and the detecting side ink chamber 123b. The actuator 106 is mounted on the top wall 1030 of the ink chamber123 b, and a porous member 1000 is provided in the detection side inkchamber 123 b as a buffer member. A coarse buffer material such asfilter can be used instead of the porous member 1000.

The airhole 2 c is provided on the top wall 1030 of the ventilation sideink chamber 123 a which ventilates with atmosphere. The check valve 228shown in FIG. 85 can be used for airhole 2 c. However, the form of theairhole 2 c is not limited to the check valve 228 shown in FIG. 85. Ifink K is consumed and the container 1 inside decreases, air isintroduced to the ventilation side ink chamber 123 a from the outside ofthe container 1 by the airhole 2 c, and the airhole 2 c thus preventsthe pressure inside the container 1 to be negative. Therefore, with theconsumption of ink advanced, air is introduced to the ventilation sideink chamber 123 a through the airhole 2 c, and the level of liquidsurface of ink K decreases.

The partition wall 193 a is coupled with the top wall 1030 and sidewall, not shown in the figure, liquid-tightly. Therefore, even the inkis consumed, ink K is sufficiently absorbed in the porous member 1000and filled in the detection side ink chamber 123 b in the container 1until the level of liquid surface of ink K reaches to the lower end 193aa of the partition wall 193 a. When the ink consumption advances, andthe level of liquid surface of ink K reaches to the lower end 193 aa ofthe partition wall 193 a, gas enters to the detection side ink chamber123 b. The ink k absorbed by the porous member 1000 in the detectionside ink chamber 123 b thereby flows out to the ink supply port 2, andthe medium existed around the actuator 106 changes from ink toatmosphere. Therefore, the actuator 106 can detect that the statusinside the ink cartridge is in ink end status. Thus, it is the lower end193 aa to determine which level of the liquid surface of ink K to be aink end. Furthermore, the volume of the detection side ink chamber 132 bis determined by the position of partition wall 193 a to the top wall1030. Therefore, the ink quantity remains inside the container 1 whendetecting the ink end can be set by the position of the partition wall193 a to the top wall 1030 and the height of the lower end 193 aa in thedirection vertical to the ink surface.

Here, the case of using an on-carriage type ink jet recording apparatus,the ink cartridge of which is move together with recording head duringthe scanning process will be considered. If there is no partition wall193 a in the container 1, or if no buffer material is provide around theactuator 106, bubbles may be generated by the waving of ink, which iscaused by the vibration of ink cartridge generated by such as thescanning operation during the printing process because the ink cartridgemoves together with recording head. Then, there is a danger that theactuator 106 may detect mistakenly that there is enough ink in thecontainer 1 if the ink attaches to the actuator 106 by the waving of inkeven if there is little amount of ink in the container 1. Moreover,there is also a danger that the actuator 106 may detect mistakenly thatthere is no ink if the bubble attaches to the actuator 106 even if theink is filled in the container 1.

However, according to the embodiment of the liquid container of thepresent embodiment, the partition wall prevents the waving of ink aroundthe piezoelectric device even when the ink cartridge vibrates by such asthe scanning operation during the printing process. By preventing thewaving of ink around the piezoelectric device, the partition wall 193 aprevents the generation of the bubbles. Furthermore, even the bubblesgenerate in the ventilation side ink chamber, the partition wallseparates the ventilation side ink chamber and the detection side inkchamber. Therefore, the partition wall prevents the bubbles to moveclose to the actuator 106 and contact with the actuator 106.

Moreover, the porous member 1000 is provided on the detection side inkchamber 123 b to intervene between the actuator 106 and the ventilationside ink chamber 123 a. Therefore, even if the bubbles generated in theventilation side ink chamber 123 a enters into the detection side inkchamber 123 b mistakenly, the porous member 1000 prevents the bubbles tomove close to the actuator 106 and contact with the actuator 106.

Furthermore, because the porous member 1000 is provided in the detectionside ink chamber 123 b, ink inside the detection side ink chamber 123 bdoes not wave by the vibration of the actuator 106. Therefore, theactuator 106 can reliably and stably detect the ink consumption statusin the container 1.

The volume of the detection side ink chamber 123 b is preferably half orsmaller than half of the volume of the ventilation side ink chamber 123a. The detection side ink chamber 123 b preferably has a width in adegree not to arise a capillary force such as to hold ink K.

The actuator 106 can be used as a means of merely detecting thevibration without vibrating itself.

There is no limitation of the size, thickness, shape, flexibility, andmaterial for the partition wall of the ink cartridge of the embodimentof the liquid container according to the present embodiment. Therefore,the size of the partition wall can be made further larger or smaller.The thickness of the partition wall can be made further thicker orthinner. Furthermore, the shape of the partition wall can be square orrectangular. Furthermore, the partition wall can be made from the hardmaterial or flexible material. For example, material such as plastic,tefron, nylon, polypropylene, or PET can be used for the partition wall.Preferably, the partition wall is made from the air-tight orliquid-tight material which does not pass through gas or liquid.Moreover, the container and the partition wall are made from samematerial so that the container and the partition wall can be formed inone body. The manufacturing process of the ink cartridge can thereby bereduced.

Moreover, there is no limitation of the size, thickness, shape,flexibility, and material for the porous member of the ink cartridge ofthe embodiment of the liquid container according to the presentembodiment. Therefore, the size of the porous member can be made furtherlarger or smaller. The thickness of the porous member can be madefurther thicker or thinner. Furthermore, the shape of the porous membercan be cubic or rectangular parallelepiped.

Moreover, there is no limitation of the shape of the hole included inthe porous member. Therefore, for example, the negative pressure orcapillary force of the porous member, which includes the hole ofspherical shape, can be increased by reducing the size of the hole. Onthe other hand, the negative pressure or capillary force of the porousmember, which includes the hole of spherical shape, can be decreased byenlarging the size of the hole. Preferably, the porous member 1000 ismade from a flexible material such as sponge. Moreover, it is preferableto set the diameter of hole of the porous member to predetermineddiameter so that the porous member can absorb ink from a cavity,referring to FIG. 19, which is formed in the actuator 106, and introduceink to ink supply port, referring to FIG. 1.

The porous member 1000 of the embodiment shown in FIG. 69 has a shape ofrectangular parallelepiped. The porous member 1000 is filled in thedetection side ink chamber 123 b such that the porous member 1100 fillsfrom the periphery of the actuator 106 to the bottom wall 1 a which islocated below the ink surface in the ink cartridge.

A packing ring 4 and a valve body 6 are provided in the ink supply port2. Referring to FIG. 70, the packing ring 4 is engaged with the inksupply needle 32 communicating with a recording head 31, in afluid-tight manner. The valve body 6 is constantly and elasticallycontacted against the packing ring 4 by way of a spring 5. When the inksupply needle 32 is inserted, the valve body 6 is pressed by the inksupply needle 32 so as to open an ink passage, so that ink inside thecontainer 1 is supplied to the recording head 31 via the ink supply port2 and the ink supply needle 32. On an upper wall of the container 1,there is mounted a semiconductor memory means 7 which stores data on inkinside the ink cartridge.

FIG. 71 is a cross sectional view of a further another embodiment of anink cartridge as an embodiment of the liquid container according to thepresent invention. An ink cartridge of the present embodiment has a topwall 1030, which locates upside of the liquid surface of ink K. Theactuators 106 are mounted on the top wall 1030 such that the actuator106 can contacts with ink through the through hole 1 c provided on thetop wall 1030. A first partition wall 193 c extends from the top wall1030 downward to the ink surface. Furthermore, the present embodimenthas a second partition wall 193 d which extends from the top wall 1030inside the detection side ink chamber 123 b and separates the detectionside ink chamber 123 b at least into two detection side small inkchambers 1123 a and 1123 b such that ink housed in both of the detectionside small ink chamber 1123 a and 1123 b can communicate each other. Theactuator 106 is mounted on the top wall 1030 of each of the detectionside small ink chambers 1123 a and 1123 b, respectively.

Furthermore, a porous member 1002 and a porous member 1003 are providedto each of the inside of the detection side small ink chamber 1123 a andthe detection side small ink chamber 1123 b.

Because gas is introduced from the airhole 128, ink is consumed from theventilation side ink chamber 123 a, which is near to the airhole 128, tothe detection side small ink chamber 1123 b, which is far from theairhole 128. Therefore, during ink in the ventilation side ink chamber123 a which is nearest to the airhole 128 is consumed, the detectionside ink chamber 123 b is filled with ink. When the ink level in theventilation side ink chamber 123 a reaches to the lower end 193 cc ofthe partition wall 193 c, air enters into the detection side small inkchamber 1123 a, and then the ink in the detection side small ink chamber1123 a is beginning to be consumed. At this time, ink is filled in thedetection side small ink chamber 1123 b. Furthermore, if the ink levelin the detection side small ink chamber 1123 a reaches to the lower end193 dd of the second partition wall 193 d, air enters into the detectionside small ink chamber 1123 b, and then the ink in the detection sidesmall ink chamber 1123 b is beginning to be consumed. In this way, inkis sequentially consumed from the ventilation side ink chamber 123 a tothe detection side small ink chamber 1123 b.

Because each of the actuators 106 is mounted on the top wall 1030 ofeach of the detection side small ink chambers 1123 a and 1123 b, theactuators 106 can detect the decrease of the ink quantity step by step.Furthermore, the volume of the detection side ink chamber 123 b issmaller than the volume of the ventilation side ink chamber 213 a.Furthermore, the volume of the detection side small ink chamber 1123 aand 1123 b gradually decreases from the detection side small ink chamber1123 a which is near to the airhole 128 to the detection side small inkchamber 1123 b, which is far from the airhole 128. Therefore, the timeinterval of detecting the decrease of the ink quantity graduallydecreases. The frequency of the ink quantity detection can thereby beincreased as the ink end is drawing near.

FIG. 72 shows further another embodiment of the ink cartridge using theactuator 106. An ink cartridge 180A shown in FIG. 72 has a partitionwall 212 a which extends downward from the top face 194 c of the inkcontainer 194. The container 194 is separated into a ventilation sideink chamber 213 a and a detection side ink chamber 213 b by thepartition wall 212 a. Because lower end 212 aa of the partition wall 212a and the bottom wall 1 a of the container 194 have a predeterminedspace, the ventilation side ink chamber 213 a and the detection side inkchamber 213 b communicates with each other.

A buffer member 1005 a is provided to block the communicating portbetween the ventilation side ink chamber 213 a and the detection sideink chamber 213 b. A filter-like material, which includes many holes onits surface, can be used for buffer member 1050 a if the buffer membercloses the communicating port. Furthermore, the buffer member can beporous member. Therefore, the ventilation side ink chamber 213 a and thedetection side ink chamber 123 b communicates each other through thebuffer member 1005 a. Because the buffer member 1005 a is made fromporous material, the buffer material pass through gas and liquid.However, if the buffer member 1005 a holds liquid by the capillaryforce, the buffer member becomes airtight. Therefore, the buffer member1050 a can suppress bubbles to passing through the buffer member 1050 a.Thus, the buffer member 1050 a can prevents the bubbles, which isgenerated in the ventilation side ink chamber 213 a, to enter inside thedetection side ink chamber 213 b and attach to the actuator 106.

The actuator 106 is mounted on the top wall 194 c of each of theventilation side ink chamber 213 a and the detection side ink chamber213 b. The volume of the detection side ink chamber 213 b is smallerthan the volume of the ventilation side ink chamber 213 a. The volume ofthe detection side ink chamber 213 b is smaller than the half of thevolume of the ventilation side ink chamber 213 a in the ink cartridge ofaccording to the present embodiment.

A buffer 214 a, that is a concave part for accepting the air bubblewhich enters to the ink cartridge 180A is formed on the top wall 194 cof the detection side ink chamber 213 b. In FIG. 72, the buffer 214 a isformed as a concave part overhang upward from the top wall 194 c of thecontainer 194. The buffer 214 a accepts the air bubble which enters intothe detection side ink chamber 213 b mistakenly when the ink is filledin the detection side ink chamber 213 b. The buffer 214 a therebyprevents the bubbles to attach to the actuator 106. Therefore, thebuffer 214 b prevents the malfunction of the actuator 106 to detect theink end wrongly by the attaching of air bubble to the actuator 106.Furthermore, the level of ink surface on which the actuator 106 detectsthe ink end can be changed by changing the length of the partition wall212 a. Furthermore, by changing the width between the partition wall 212a and the side wall 194 b, the predetermined ink quantity remained afterthe detection of the ink end can be changed.

The ink cartridge 180B shown in FIG. 73 fills a porous member 1005 b inthe detection side ink chamber 123 b of the ink cartridge 180A shown inFIG. 72. The porous member 1005 b is filled inside the detection sideink chamber 213 b from the top wall 194 c to the bottom wall 194 a. Theporous member 1005 b contacts with the actuator 106. There is a casethat the actuator 106 malfunctions by the entering of the air inside thedetection side ink chamber 213 b when the ink cartridge fall down orwhen the detection side ink chamber 213 b moves back and forth with thecarriage. If the porous member 1005 b is provided on the detection sideink chamber 213 b, the porous member 1005 b captures air to prevententering of air into the actuator 106. Furthermore, because the porousmember 1005 b holds ink, the porous member 1005 b can prevent theactuator 106 to malfunction as detecting the ink end status as ink existstatus which is caused by attaching of the ink on the actuator 106 whenthe ink container rolls. The ink quantity which can be consumed afterthe detection of the ink end can be changed by adjusting the volume ofthe detection side ink chamber 213 b by changing the width between theside wall 194 b and the partition wall 212 a. Furthermore, the level ofink surface on which the actuator 106 detects the ink end can be changedby adjusting the height of the lower end 212 aa of the partition wall212 a from the ink surface.

FIG. 74 shows an ink cartridge 180C, the porous member of which isconstituted by two kinds of porous members 1005 c and 1005 d having adifferent hole diameter with each other. The porous member 1005 c islocated closer to the actuator 106 than the porous member 1005 d. Thehole diameter of the porous member 1005 c is larger than the holediameter of the porous member 1005 d. The capillary force of the porousmember 1005 d, which has small hole diameter, is larger than thecapillary force of the porous member 1005 c, which has large holediameter. Therefore, the ink, which once flows from the porous member1005 c to the porous member 1005 d, does not flow backward to the porousmember 1005 c because the capillary force works at the porous member1005 d. Therefore, the porous members 1005 c and 1005 d prevents theattaching of ink to the actuator 106 by the waving of ink and therebyprevents the malfunction of the actuator 106 to detect the ink endstatus as ink exist status. The porous member 1005 c can be formed bythe material which has a lower affinity for liquid than the affinity forliquid of the material which forms the porous member 1005 d.

FIG. 75 shows a cross section of an ink cartridge 180D which is furtherother embodiment of the ink cartridge 180 using actuator 106. Ribs 1100,which protrudes inside the ink container 194, are provided on the bottomside of the side wall 194 b of the detection side ink chamber 213 b. Theporous member 1005 b which is provided inside the detection side inkchamber 213 b is gradually compressed by the ribs 1100 such that thearea of the cross section on the horizontal plane of the porous member1005 b gradually decreases downwards along the vertical direction.Therefore, the hole diameter of the porous member 1005 b decreasesgradually in the direction downward to the ink surface. Because the holediameter of the lower part of the porous member 1005 b reduced by theribs 1100, the ink, which once flows into the lower part of the porousmember 1005 b does not flow backward to the upside of the porous member1005 b by the capillary force. Furthermore, the porous member 1005 b ofthe present embodiment prevents ink to attach to the actuator 106, whichis mounted on the top wall 194 c, by the waving of ink. Therefore, themalfunction of the actuator 106 to detect the ink end status as the inkexist status can be prevented.

FIG. 76(A) and FIG. 76(B) shows further another embodiment of the inkcartridge using actuator 106. FIG. 76(A) is a cross sectional view alongthe longitudinal direction of a ink cartridge 180E. FIG. 76(B) shows B-Bcross sectional view of the ink cartridge 180E shown in FIG. 76(A). Ataper 1110 is provided on the lower side of the side wall of thedetection side ink chamber 213 b. The width of the detection side inkchamber 213 b gradually narrows downward along the vertical direction bythe taper 1110. Therefore, the porous member 1005 b is compressedgradually by the taper 1110 such that the area of the cross section onthe horizontal plane of the porous member 1005 b gradually decreasesdownwards along the vertical direction. Therefore, lower side of thehole diameter of the porous member 1005 b gradually becomes smaller thanthe upper side of the hole diameter of the porous member 1005 b by thetaper 1110. Because the hole diameter of the lower part of the porousmember 1005 b reduced by the taper 1110, the ink, which once flows intothe lower part of the porous member 1005 b does not flow backward to theupside of the porous member 1005 b by the capillary force. Furthermore,the porous member 1005 b of the present embodiment prevents ink toattach to the actuator 106, which is mounted on the top wall 194 c, bythe waving of ink. Therefore, the malfunction of the actuator 106 todetect the ink end status as the ink exist status can be prevented.

FIG. 77 shows further another embodiment of the ink cartridge usingactuator 106. An ink cartridge 180F shown in FIG. 77 has a partitionwall 212 c which is sloped toward the ink surface. A porous member 1105e is filled in the detection side ink chamber 213 b. The partition wall212 c extends from a top wall 194 c. The distance between the side wall194 b of the ink cartridge 180C and the partition wall 212 c graduallynarrows toward downside. Therefore, the porous member 1005 e iscompressed gradually by the partition wall 212 c such that the area ofthe cross section on the horizontal plane of the porous member 1005 bgradually decreases toward downside. Therefore, lower side of the holediameter of the porous member 1005 e gradually becomes smaller than theupper side of the hole diameter of the porous member 1005 e by thepartition wall 212 c. Because the hole diameter of the lower part of theporous member 1005 e is reduced by the partition wall 212 c, the ink,which once flows into the lower part of the porous member 1005 e doesnot flow backward to the upside of the porous member 1005 e by thecapillary force. Furthermore, the porous member 1005 e of the presentembodiment prevents ink to attach to the actuator 106, which is mountedon the top wall 194 c, by the waving of ink. Therefore, the malfunctionof the actuator 106 to detect the ink end status as the ink exist statuscan be prevented.

Moreover, gas existed in the ventilation side ink chamber 213 a isdifficult to enter into the detection side ink chamber 213 b. Therefore,the malfunction caused by the attaching of bubble to the actuator 106can be further prevented. Furthermore, a gap is provided between thelower end 212 cc and the bottom wall 2 a of the ink cartridge 180F. Acapillary force, which can hold ink, does not work on the gap providedbetween the lower end 212 cc and the side wall 194 b.

FIG. 78 shows further another embodiment of the ink cartridge using theactuator 106. An ink cartridge 180G shown in FIG. 78 has a partitionwall 212 b which is formed in L-shape. The partition wall 212 b extendsfrom a top wall 194 c. A lower end 212 bb of the partition wall 212 b islonger than the lower end 212 aa of the partition wall 212 a in theembodiment shown in FIG. 72 to FIG. 77. A porous member 1005 f is filledin the detection side ink chamber 213 b.

A porous member 1005 g, which is a bottom part of porous member 1005 f,is sandwiched and compressed by the lower end 212 bb and the side wall194 b. Therefore, the hole diameter of the porous member 1005 g issmaller than the hole diameter of the porous member 1005 f. Thus, thehole diameter of the porous member decreases from the porous member 1005f, which locates nearby the actuator 106, to the porous member 1005 gand further to porous member 1005 h. The hole diameter of the porousmember 1005 f thereby decreases step by step downward to the inksurface. Therefore, the ink, which once flows into the lower part of theporous member 1005 f does not flow backward to the upside of the porousmember 1005 f by the capillary force. Furthermore, the porous member1005 f of the present embodiment prevents ink to attach to the actuator106, which is mounted on the top wall 194 c, by the waving of ink.Therefore, the malfunction of the actuator 106 to detect the ink endstatus as the ink exist status can be prevented.

Moreover, the bottom end 212 bb is longer than the lower end 212 aa ofthe partition wall 212 a of the embodiments shown in FIG. 72 to FIG. 77.Therefore, gas existed in the ventilation side ink chamber 213 a isdifficult to enter into the detection side ink chamber 213 b. Therefore,the malfunction of the actuator 106 to detects the ink end wronglycaused by the attaching of bubble to the actuator 106 can be furtherprevented. Furthermore, a gap is provided between the lower end 212 bband the bottom wall 2 a. A capillary force, which can hold ink, does notwork on the gap provided between the lower end 212 bb and the bottomwall 2 a.

FIG. 79 shows further another embodiment of the ink cartridge 180. Anink cartridge 180H shown in FIG. 79 has a first partition wall 212 dwhich extends downward from the top face 194 c of the ink container 194.Furthermore, a second wall extends from the first partition wall 212 dtoward the side wall 194 b substantially parallel to the ink surface.The container 194 is separated into a ventilation side ink chamber 213 aand a detection side ink chamber 213 b by the first partition wall 212d. Furthermore, the second partition wall 212 e separates the detectionside ink chamber into a first detection side ink chamber 213 c and asecond detection side ink chamber 213 d. A gap is provided between thebottom wall 2 a and the lower end 212 dd of the first partition wall 212d. Furthermore, a gap is provided between the side wall 194 b and theone end 212 ee of the second partition wall 212 e. A concave part isprovided on a part of top wall 194 c to form a buffer 214 a whichaccepts the bubble. Furthermore, porous member 1005 i is filled insidethe first detection side small ink chamber 213 c. One end 212 ee of thesecond partition wall 212 e, which extends toward the side wall 194 b,extends until to the position where just under the buffer 214 b.

Therefore, first, the first partition wall 212 d prevents the enteringof bubble into the first detection side ink chamber 213 c. If the bubbleenters into the detection side ink chamber 213 c mistakenly, the bubbleis absorbed by the porous member 1005 i. Furthermore, if the bubblereaches to the second partition wall 212 e, the bubble is introduced tothe position which is just under the buffer 214 a by the secondpartition wall 212 e. Therefore, the bubble is caught by the buffer 214a. Therefore, the malfunction of the actuator 106 to detects the ink endwrongly by the attaching of bubble to the actuator 106, which isprovided in the second detection side ink chamber 213 d, can be furtherprevented.

FIG. 80 shows further another embodiment of the ink cartridge 180. Anink cartridge 180I shown in FIG. 80 has a partition wall 212 a as sameas the partition wall 212 a of FIG. 72. The partition wall 212 a extendsdownward from the top face 194 c of the ink container 194. The container194 is separated into a ventilation side ink chamber 213 a and adetection side ink chamber 213 b by the partition wall 212 a. A gap isprovided between the bottom wall 1 a and the partition wall 212 a. Aporous member 1005 b is provided inside the detection side ink chamber213 b. Furthermore, a concave part is provided on a part of top wall 194c to form a buffer 214 b which accepts the bubble. A tapered face 1040is provided between the buffer 214 b and the actuator 106.

Therefore, first, the partition wall 212 a prevents the entering ofbubble into the detection side ink chamber 213 b. If the bubble entersinto the detection side ink chamber 213 b mistakenly, the bubble isabsorbed by the porous member 1005 b. If the bubble reaches to the upperside of the detection side ink chamber 213 b, the bubble is directlycaught by the buffer 214 a or introduced to the buffer 214 b along thetapered face 1040. Therefore, the malfunction of the actuator 106 todetects the ink end wrongly by the attaching of bubble to the actuator106 can be further prevented. The shape and size of the buffer can beother arbitrary shape and size.

Moreover, the second partition wall 212 e in the embodiment shown inFIG. 79 can be provided on the ink cartridge 1801 of the embodimentshown in FIG. 80 such that the second partition wall 212 e extends fromthe first partition wall 212 a toward the side wall 214 b in thedirection parallel to the ink surface. In this case, one end 212 ee ofthe second partition wall 212 e is extended to the position just underthe taper face 1040.

FIG. 82 shows further another embodiment of the ink cartridge 180 usingactuator 106. An ink cartridge 180K shown in FIG. 82 has a protrudingpart 214 f, which protrudes inside the container 194, on a part of thetop wall 194 c. The actuator 106 is mounted on the bottom part of theprotruding part 214 f. A partition wall 212 f extends downward from thetop face 194 c. A buffer 214 c is provided for each of the positionbetween the actuator 106 and the partition wall 212 a and between theactuator 106 and the side wall 194 b. Therefore, the periphery of theactuator 106 is surrounded by the buffer 214 c. A porous member 1005 bis provided inside the detection side ink chamber 213 b. By providingthe actuator 106 on the protruding part 214 f, positioning for mountingthe actuator 106 on the ink cartridge 180J becomes easier whenmanufacturing the ink cartridge 180J.

FIG. 82 shows further another embodiment of the ink cartridge 180 usingactuator 106. An ink cartridge 180K shown in FIG. 82 has a partitionwall 212 a extends downward from the top face 194 c. The container 194is separated into a ventilation side ink chamber 213 a and a detectionside ink chamber 213 b by the partition wall 2129. Uneven part isprovided on the top wall 194 c, and two actuators 106 are mounted on theprotruding part which protrudes inside the detection side ink chamber213 b. The concave part of the top wall 194 c works as a buffer 214 cwhich accepts bubble. Furthermore, a porous member 1005 b is providedinside the detection side ink chamber 213 b. By providing two actuators106 on the protruding part 214 f, detecting the ink consumption statusmistakenly can be prevented. The number of the actuators 106 can be morethan three. Moreover, as shown in FIG. 81, positioning for mounting theactuator 106 on the ink cartridge 180K becomes easier when manufacturingthe ink cartridge 180K. The number of uneven part and the number of theactuator 106 can be further increased.

FIG. 83 shows further other embodiment of the ink cartridge 180 usingactuator 106. The ink cartridge 180M shown in FIG. 83 has a plurality ofpartition walls 212 f, 212 g, 212 h, and 212 i, each of which extendsdownward from the top face 194 c of the ink container 194. The partitionwall 212 f is first partition wall, and the partition walls 212 g, 212h, and 212 i are the second partition walls. Because each of lower ends212 ff, 212 gg, 212 hh, and 212 ii of each of the partition walls 212 f,212 g, 212 h, and 212 i and the bottom wall 2 a of the container 194have a predetermined gap, the bottom part of the container 194communicates with each other. The ink cartridge 180M has a ventilationside ink chamber 213 a and a plurality of detection side small inkchambers 213 f, 213 g, 213 h, and 213 i separated by the each ofplurality of partition walls 212 f, 212 g, 212 h and 212 i. The bottompart of a plurality of the detection side small ink chambers 213 f, 213g, 213 h, and 213 i communicate with each other. Each of the actuators106 f, 106 g, 106 h, and 106 i is mounted on the top face 194 c of eachof the plurality of the detection side small ink chambers 213 f, 213 g,213 h, and 213 i, respectively. Each of the actuators 106 f, 106 g, 106h, and 106 i is arranged on substantially center of the top face 194 cof each of the plurality of the detection side small ink chambers 213 f,213 g, 213 h, and 213 i, respectively.

The volume of the ventilation side ink chamber 213 a, and the detectionside small ink chamber 213 f, 213 g, 213 h, and 213 i are graduallydecreases as the distance from the airhole 128 increases to the innerside of the ink container 194. Therefore, the volume of the ink chambersgradually decreases in the order from the ventilation side ink chamber213 a, the detection side small ink chamber 213 f, 213 g, 213 h, and 213i. Therefore, the interval of the mounting position of the actuator 106is wider on the airhole 128 side and becomes narrower as the distancefrom the airhole increases to the inner side of the ink container 194.

Furthermore, each of the porous members 1005 f, 1005 g, 1005 h and 1005i are filled in the each of the detection side small ink chambers 213 f,213 g, 213 h, and 213 i. The each of the porous members 1005 f, 1005 g,1005 h and 1005 i are filled from the detection side small ink chambers213 f, which is near to the airhole 128, to the detection side small inkchamber 213 i, which is far from the airhole 128, sequentially. Theporous members are designed such that the hole diameter increases in theorder from the porous member 1005 f, 1005 g, 1005 h and 1005 i. Theporous members can be formed such that the affinity for ink decreases inthe order from the porous member 1005 f, 1005 g, 1005 h and 1005 i.

Because gas is introduced from the airhole 128, ink is consumed from theventilation side ink chamber 213 a of the airhole 128 side to thedetection side ink chamber 213 i. For example, the ink in theventilation side ink chamber 213 a which is nearest to the airhole 128is consumed, and during the ink level of the ventilation side inkchamber 213 a decreases, the other detection side small ink chambers 213f, 213 g, 213 h, and 213 i are filled with ink. When the ink level inthe ventilation side ink chamber 213 a reaches to the lower end 212 ttof the partition wall 212 f, air enters into the detection side smallink chamber 213 f, and then the ink in the detection side small inkchamber 213 f is beginning to be consumed. The ink level in thedetection side small ink chamber 213 f thereby begin to decrease. Atthis time, ink is filled in the detection side small ink chambers 213 g,213 h, and 213 i. In this way, ink is sequentially consumed from theventilation side ink chamber 213 a to the detection side small inkchamber 213 i.

Furthermore, the porous members are designed such that the hole diameterincreases in the order from the porous members 1005 f, 1005 g, 1005 hand 1005 i. Therefore, ink is consumed in the order from the detectionside small ink chamber 213 f which is relatively near to the airhole 128to the detection side small ink chamber 213I which is far from theairhole 128, sequentially. Moreover, the porous members 1005 f, 1005 g,1005 h and 1005I prevent ink to flow back from the detection side smallink chamber 213 f to the detection side small ink chamber 213 i.

In the present embodiment, each of the actuators 106 f, 106 g, 106 h,and 106 i is mounted on the top wall 194 c of each of the detection sidesmall ink chambers 213 f, 213 g, 213 h, and 213I with interval.Therefore, the actuators 106 f, 106 g, 106 h, and 106 i can detect thedecrease of the ink quantity step by step. Furthermore, the volume ofthe ink chambers decreases from the ventilation side ink chamber 213 ato the detection side small ink chamber 213 i gradually. Therefore, thetime interval of detecting the decrease of the ink quantity graduallydecreases. Therefore, the frequency of the ink quantity detection can beincreased as the ink end is drawing near.

Furthermore, each of the volume of the detection side small ink chambercan be changed by changing the length of the partition wall as in theembodiment shown in FIG. 87.

FIG. 84 shows further other embodiment of the ink cartridge 180 usingactuator 106. In the ink cartridge 180N shown in FIG. 84, porous members1006 f, 1006 g, 1006 h and 1006 i are provided in the ink cartridge 180Nsuch that each porous members 1006 f, 1006 g, 1006 h and 1006 i closesthe each of the communication port of the ventilation side ink chamber213 a, the detection side small ink chambers 213 f, 213 g, 213 h, and213 i. Each of the ventilation side ink chamber 213 a, the detectionside small ink chambers 213 f, 213 g, 213 h, and 213 i communicates eachother through the porous members 1006 f, 1006 g, 1006 h and 1006 i.Therefore, the porous members prevent the bubble, which is generated inthe ink container 194, to enter into the ventilation side ink chamber213 a, the detection side small ink chambers 213 f, 213 g, 213 h, and213 i. Therefore, even if the bubble generates in one of the detectionside ink chambers, and one of the actuators 106 f, 106 g, 106 h, and 106i detects the ink end status mistakenly, the other actuators 106 f, 106g, 106 h, and 106 i do not detect the ink end status mistakenly.

FIG. 85 shows further other embodiment of the ink cartridge using theactuator 106. The ink cartridge 220A shown in FIG. 85 has a firstpartition wall 222 provided such that it extends downward from the topwall of the ink cartridge 220A. Because there is a predetermined spacebetween the lower end of the first partition wall 222 and the bottomwall 3 a of the ink cartridge 220A, ink can flows into the ink supplyport 230 through the bottom wall 3 a of the ink cartridge 220A. A secondpartition wall 224 is formed such that the second partition wall 224extends upward from the bottom wall 3 a of the ink cartridge 220A on themore ink supply port 230 side of the first partition wall 222. Becausethere is a predetermined space between the upper end of the secondpartition wall 224 and the top wall 221 of the ink cartridge 220A, inkcan flows into the ink supply port 230 through the top wall 221 of theink cartridge 220A.

A ventilation side ink chamber 225 a is formed relatively near to theairhole 233. On the other hand, a detection side ink chamber 225 b isformed relatively far from the airhole 233. By the second partition wall224, the detection side ink chamber 225 b and a detection side small inkchamber 227 are formed. The detection side small ink chamber 227 isformed between the first partition wall 222 and the second partitionwall 224. The detection side small ink chamber 227 is formed byproviding a gap, which can generate the capillary phenomenon, betweenthe first partition wall 222 and the second partition wall 224.Therefore, the ink in the ventilation side ink chamber 225 a iscollected to the detection side small ink chamber 227 by the capillaryforce of the detection side small ink chamber 227. Therefore, thedetection side small ink chamber 227 can prevent that the air bubble toenter into the detection side ink chamber 225 b. Furthermore, the inklevel in the detection side ink chamber 225 b can decrease steadily andgradually.

Moreover, a porous member 1005 g is provided inside the detection sideink chamber 225 b. The volume of the ventilation side ink chamber 225 ais larger than the volume of the detection side ink chamber 225 b.Because the ventilation side ink chamber 225 a is formed closer to theairhole 223 than the detection side small ink chamber 225 b, the ink inthe detection side small ink chamber 225 b is consumed after the ink inthe ventilation side ink chamber 225 a is consumed. Furthermore, thewaving of ink inside the detection side small ink chamber 225 b isprevented by providing the porous member 1005 g inside the detectionside small ink chamber 225 b. Moreover, the porous member 1005 gprevents the bubble, which is entered from the ink supply port 230, toattach to the actuator 106.

Furthermore, the capillary force of the porous member 1005 g is greaterthan the capillary force of the detection side small ink chamber 227.The porous member 1005 g thereby prevents ink to flow back from the inksupply port 230 to the ventilation side small ink chamber 225 a. Thecapillary force of the porous member 1005 g can be increased byadjusting the hole diameter. Moreover, the capillary force of the porousmember 1005 g can be increased by compressing the porous member 1005 g.

A airhole 233 is provided on the top wall of the ink cartridge 220A.Moreover, a check valve 228 is provided on the airhole 233 forpreventing the leaking of ink from the airhole 233. The leaking of inkoutside the ink cartridge 220A caused by the rolling of the inkcartridge 220A can be prevented by the check valve 228. Furthermore, theevaporation of ink from the airhole 233 of the ink cartridge 220A can beprevented by providing the check valve 228 on the top face of the inkcartridge 220A. If ink in the ink cartridge 220A is consumed, andnegative pressure inside the ink cartridge 220A exceeds the pressure ofthe check valve 228, the check valve 228 opens and introduces air intothe ink cartridge 220A. Then the check valve 228 closes to acceleratethe drainage of ink from the ink cartridge 220A.

Here, a piezoelectric device as an embodiment of a liquid censor will beexplained. The piezoelectric device, or actuator, detects a state of theliquid inside a liquid container by utilizing vibration phenomena. Thestate of the liquid includes whether or not the liquid in the liquidcontainer is empty, amount of the liquid, level of the liquid, types ofthe liquid and combination of liquids. Several specific methodsrealizing for detection of the state of the liquid inside the liquidcontainer utilizing vibration phenomena are considered. For example, amethod is considered in which the medium and the change of its stateinside the liquid container are detected in such a manner that anelastic wave generating device generates an elastic wave inside theliquid container, and then the reflected wave which is thus reflected bythe liquid surface or a wall disposed counter thereto is captured. Thereis another method in which a change of acoustic impedance is detected byvibrating characteristics of a vibrating object. As a method utilizingthe change of the acoustic impedance, a vibrating portion of apiezoelectric device or an actuator having a piezoelectric elementtherein is vibrated. Thereafter, a resonant frequency or an amplitude ofthe back electromotive force waveform is detected by measuring the backelectromotive force which is caused by residual vibration which remainsin the vibrating portion, so as to detect the change of the acousticimpedance. As another method utilizing the change of the acousticimpedance, the impedance characteristic or admittance characteristic ofthe liquid is measured by a measuring apparatus such as an impedanceanalyzer and a transmission circuit, so that the change of a currentvalue or a voltage value, or the change of the current value or voltagevalue due to the frequency caused by the vibration given to the liquidis measured. In the present embodiment, the actuator 106 can detect theliquid status inside the liquid container by any method mentioned above.

FIG. 86 shows further other embodiment of the ink cartridge 180. FIG. 86shows a cross section of an ink cartridge 180P. The semiconductor memorydevice 7 and the actuator 106 are formed on the same circuit board 610in the ink cartridge 180P.

A different-type O-ring 614 is mounted on the side wall 194 b such thatthe different-type O-ring 614 surrounds the actuator 106. A plurality ofcaulking part 616 is formed on the side wall 194 b to couple the circuitboard 610 with the container 194. By coupling the circuit board 610 withthe container 194 using the caulking part 616 and pushing thedifferent-type O-ring 614 to the circuit board 610, the vibrating regionof the actuator 106 can contacts with ink, and at the same time, theinside of the ink cartridge is sealed from outside of the ink cartridge.

A terminals 612 are formed on the semiconductor memory device 7 andaround the semiconductor memory device 7. The terminal 612 transfer thesignal between the semiconductor memory device 7 and outside the ink jetrecording apparatus. The semiconductor memory device 7 can beconstituted by the semiconductor memory which can be rewritten such asEEPROM. Because the semiconductor memory device 7 and the actuator 106are formed on the same circuit board 610, the mounting process can befinished at one time during mounting the semiconductor memory device 7and the actuator 106 on the ink cartridge 180P. Moreover, the workingprocess during the manufacturing of the ink cartridge 180C and therecycling of the ink cartridge 180P can be simplified. Furthermore, themanufacturing cost of the ink cartridge 180P can be reduced because thenumbers of the parts can be reduced.

The actuator 106 detects the ink consumption status inside the container194. The semiconductor memory device 7 stores the information of inksuch as residual quantity of ink detected by the actuator 106. That is,the semiconductor memory device 7 stores the information related to thecharacteristic parameter such as the characteristic of ink and the inkcartridge used for the actuator 106 when detecting the ink consumptionstatus. The semiconductor memory device 7 previously stores the resonantfrequency of when ink inside the container 194 is full, that is, whenink is filled in the container 194 sufficiently, or when ink in thecontainer 194 is end, that is, ink in the container 194 is consumed, asone of the characteristic parameter. The resonant frequency when the inkinside the container 194 is full status or end status can be stored whenthe ink container is mounted on the ink jet recording apparatus for thefirst time. Moreover, the resonant frequency when the ink inside thecontainer 194 is full status or end status can be stored during themanufacturing of the container 194. Because the unevenness of thedetection of the residual quantity of ink can be compensated by storingthe resonant frequency when the ink inside the container 194 is fullstatus or end status in the semiconductor memory device 7 previously andreading out the data of the resonant frequency at the ink jet recordingapparatus side, it can be accurately detected that the residual quantityof ink is decreased to the reference value.

FIG. 87 shows further other embodiment of the ink cartridge 180. The inkcartridge 180Q shown in FIG. 87 has a plurality of partition walls 212p, 212 q, and 212 r. The partition walls 212 p, 212 q, and 212 rseparates the ink container 194 into the ventilation side ink chamber213 a and the detection side small ink chamber 213 p, 213 q, and 213 r.The partition wall 212 p is the first partition wall, and the partitionwalls 212 q and 212 r are the second partition walls. Each of porousmembers 1005 p, 1005 q, and 1005 r are provided in the each of thedetection side small ink chamber 213 p, 213 q, and 213 r. Furthermore,each of partition walls 212 p, 212 q, and 212 r are provided on the topwall 194 c with substantially equal intervals. Furthermore, each of thepartition walls 212 p, 212 q, and 212 r extends from the top wall 194 ctoward the bottom wall 2 a. Each of the partition walls 212 p, 212 q,and 212 r have different length. Moreover, the length of the partitionwalls 212 p, 212 q, and 212 r increases in the order of the partitionwall 212 p, 212 q, and 212 r. Therefore, even the interval between theeach of the partition walls 212 p, 212 q, and 212 r is different, thevolume of the each of the detection side small ink chambers aredifferent with each other.

Because the length of each of the partition walls 212 p, 212 q, and 212r increases with the increase of the distance from the airhole 128, gasis most difficult to enter into the detection side small ink chamber 213r which is farthest from the airhole 128. Therefore, the actuator 106 rcan detect the ink existence most accurately among the actuators 106 p,106 q, and 106 r which is mounted on the each of the detection sidesmall ink chamber 213 p, 213 q, and 213 r.

FIG. 88 shows an embodiment around a recording head of part of the inkcartridge and an ink jet recording apparatus which uses the actuator106. In the present embodiment, the ink cartridge 180A shown in FIG. 72is used. However, the ink cartridge in any of the ink cartridge shown inFIG. 73 to FIG. 84 also can be used. Furthermore, the ink cartridge ofthe other form also can be used. A plurality of ink cartridges 180A ismounted on the ink jet recording apparatus which has a plurality of inkintroducing members 182 and a holder 184 each corresponding to the eachof ink cartridge 180, respectively. Each of the plurality of inkcartridges 180A contains different types of ink, for example, differentcolor of ink. The actuator 106, which detects at least acousticimpedance, is mounted on the each of top wall of the plurality of inkcartridge 180A. The actuator 106, a partition wall 212 a, and a porousmember 1005 b are provided for each top wall of the plurality of inkcartridge 180A. The residual quantity of ink in the ink cartridge 180can be detected by mounting the actuator 106 on the ink cartridge 180.The partition wall 212 a prevents the waving and bubbling of ink.

FIG. 89 shows a detail around the head member of the ink jet recordingapparatus. In the present embodiment, the ink cartridge 180A shown inFIG. 72 is used. However, the ink cartridge in any of the ink cartridgeshown in FIG. 73 to FIG. 84 also can be used. Furthermore, the inkcartridge of the other form also can be used. The ink jet recordingapparatus has an ink introducing member 182, a holder 184, a head plate186, and a nozzle plate 188. A plurality of nozzle 190, which jet outink, is formed on the nozzle plate 188. The ink introducing member 182has an air supply hole 181 and an ink introducing inlet 183. The airsupply hole 181 supplies air to the ink cartridge 180. The inkintroducing inlet 183 introduces ink from the ink cartridge 180A. Theink cartridge 180A has an air introducing inlet 185 and an ink supplyport 187. The air introducing inlet 185 introduces air from the airsupply hole 181 of the ink introducing member 182. The ink supply port187 supplies ink to the ink introducing inlet 183 of the ink introducingmember 182. By introducing air from the ink introducing member 182 tothe ink cartridge 180, the ink cartridge 180 accelerates the supply ofink from the ink cartridge 180A to the ink introducing member 182. Theholder 184 communicates ink, which is supplied from the ink cartridge180A through the ink introducing member 182, to the head plate 186. Inkis supplied to the head from the ink cartridge 180A through the inkintroducing member 182 and discharged to the recording medium fromnozzle. In this way, the ink jet recording apparatus performs theprinting on the recording medium.

FIG. 90 is a cross sectional view of an embodiment of an ink cartridgefor use with a single color, for example, the black ink. In the inkcartridge shown in FIG. 90, the detection method implemented is based ona method, among methods described above, in which the position of theliquid surface in the liquid container and whether or not the liquid isempty are detected by receiving the reflected wave of the elastic wave.As a means for generating and receiving the elastic wave, an elasticwave generating device 3 is utilized. An ink supply port 2 which comesin contact with an ink supply needle of the recording apparatus in asealed manner is provided in a container 1 which houses the ink. In anoutside portion of a bottom face 1 a of the container 1, the elasticwave generating device 3 is mounted such that the elastic wave can becommunicated, via the container, to the ink inside the container. Inorder that at a stage at which the ink K is almost used up, i.e. at thetime when the ink becomes an ink-end state, the transfer of the elasticwave can change from the liquid to the gas, the elastic wave generatingdevice 3 is provided in a slightly upward position from the ink supplyport 2. Moreover, an elastic wave receiving means may be separatelyprovided instead, so that the elastic wave generating device 3 is usedas an elastic wave generating device only.

A packing ring 4 and a valve body 6 are provided in the ink supply port2. Referring to FIG. 91, the packing ring 4 is engaged with the inksupply needle 32 communicating with a recording head 31, in afluid-tight manner. The valve body 6 is constantly and elasticallycontacted against the packing ring 4 by way of a spring 5. When the inksupply needle 32 is inserted, the valve body 6 is pressed by the inksupply needle 32 so as to open an ink passage, so that ink inside thecontainer 1 is supplied to the recording head 31 via the ink supply port2 and the ink supply needle 32. On an upper wall of the container 1,there is mounted a semiconductor memory means 7 which stores data on inkinside the ink cartridge.

Furthermore, a porous member 1050 is provided inside the container 1. Agap is provided between the porous member 1050 and the elastic wavegenerating device 3 to form an ink layer. By providing the porous member1050 inside the container 1, the porous member 1050 prevents the wavingor bubbling of ink inside the container 1 when the ink cartridge movestogether with the recording head by the scanning operation during theprinting process. Therefore, the bubble and wave of ink is difficult togenerate around the elastic wave generating device 3, the elastic wavegenerating device 3 can accurately detect the ink consumption status.

Furthermore, the hole diameter of porous member 1050 is set such thatthe porous member 1050 does not absorbs ink existed in the ink layer1060 when the ink surface reaches to the ink layer 1060 by theconsumption of ink inside the container 1. In other words, the porousmember 1050 is designed such that the capillary force works in theporous member 1050 does not hold ink in the container 1. Therefore, inkdoes not remain in the porous member 1050 by its own weight and remainsin the ink layer 1060 when the ink inside the container 1 is in an inknear end status.

An airhole, not shown in the figure, is provided on the container 1. Theairhole is provided on the upper side of the ink surface to communicatewith outside of container 1. Air is introduced inside the container 1 bythe airhole, and ink flows downward by its own weight with advance ofink consumption. The residual ink thereby stays in the ink layer 1060.Because the porous member 1050 is provided inside the container 1, theelastic wave generating device 3 can detect the ink quantity only whenthe ink status is near to the ink end if the width of the ink layer issmall. However, ink does not wave by providing the porous member 1050 inthe container 1. Therefore, the elastic wave generating device 3 candetect the ink surface accurately when the ink surface inside thecontainer 1 reaches to the lower end of the porous member 1050, and inksurface exists within the ink layer 1060.

Moreover, the width of the gap between the porous member 1050 and theelastic wave generating device 3 is not limited. To suppress thebubbling of ink as much as possible, the width of ink layer 1060 isreduced by providing the porous member 1050 on lower side of thecontainer 1. If the width of the ink layer 1060 is small, the elasticwave generating device 3 can detect the ink quantity only when the inkstatus is near to the ink end. However, ink does not wave inside thecontainer 1. Therefore, the elastic wave generating device 3 canaccurately detect the ink quantity and existence of ink when the inkconsumption status is near to the ink end status. Therefore, the porousmember 1050 is preferably located nearby the elastic wave generatingdevice 3 without limiting the width of gap between the porous member1051 and elastic wave generating device 3. Moreover, even the bubble ofink generates, because the bubble of ink is absorbed in the porousmember 1050, the bubble does not stays around the elastic wavegenerating device 3. The porous member 1050 thereby prevents the elasticwave generating device 3 to detect the ink consumption statusmistakenly.

FIG. 91 is a cross sectional view showing an embodiment of a major partof the ink-jet recording apparatus suitable for the ink cartridge shownin FIG. 90. A carriage 30 capable of reciprocating in the direction ofthe width of the recording paper is equipped with a subtank unit 33,while the recording head 31 is provided in a lower face of the subtankunit 33. Moreover, the ink supply needle 32 is provided in an inkcartridge mounting face side of the subtank unit 33.

While the recording apparatus is operating, a drive signal is suppliedto the elastic wave generating device 3 at a detection timing which isset in advance, for example, at a certain period of time. The elasticwave generated by the elastic wave generating device 3 is transferred tothe ink by propagating through the bottom face 1 a of the container 1 soas to be propagated to the ink.

By adhering the elastic wave generating device 3 to the container 1,since a process of embedding electrodes for use in detecting the liquidsurface is unnecessary in the course of forming the container 1, aninjection molding process can be simplified and the leakage of theliquid from a place in which the electrodes are supposedly embedded canbe avoided, thus improving the reliability of the ink cartridge.

Furthermore, a porous member 1050 is provided inside the container 1. Byproviding the porous member 1050 inside the container 1, the porousmember 1050 prevents the waving or bubbling of ink inside the container1 when the ink cartridge moves together with the recording head by thescanning operation during the printing process. Because the bubble andwave of ink is difficult to generate around the elastic wave generatingdevice 3, the elastic wave generating device 3 can accurately detect theink consumption status.

FIG. 92 is a detailed cross sectional view of a subtank unit 33. Thesubtank unit 33 comprises the ink supply needle 32, the ink chamber 34,a flexible valve 36 and a filter 37. In the ink chamber 34, the ink ishoused which is supplied from the ink cartridge via ink supply needle32. The flexible valve 36 is so designed that the flexible valve 36 isopened and closed by means of the pressure difference between the inkchamber 34 and the ink supply passage 35. The subtank unit 33 is soconstructed that the ink supply passage 35 is communicated with therecording head 31 so that the ink can be supplied up to the recordinghead 31.

Referring to FIG. 91, when the ink supply port 2 of the container 1 isinserted through the ink supply needle 32 of the subtank unit 33, thevalve body 6 recedes against the spring 5, so that an ink passage isformed and the ink inside the container 1 flows into the ink chamber 34.At a stage where the ink chamber 34 is filled with ink, a negativepressure is applied to a nozzle opening of the recording head 31 so asto fill the recording head with ink. Thereafter, the recording operationis performed.

When the ink is consumed in the recording head 31 by the recordingoperation, a pressure in the downstream of the flexible valve 36decreases. Then, the flexible valve 36 is positioned away from a valvebody 38 so as to become opened. When the flexible valve 36 is opened,the ink in the ink chamber 34 flows into the recording head 31 throughthe ink passage 35. Accompanied by the ink which has flowed into therecording head 31, the ink in the container 1 flows into the subtankunit 33 via the ink supply needle 32.

According to the embodiment shown in FIG. 91 and FIG. 92, the elasticwave generating device 3 and the porous member 1050 are provided also inthe subtank unit 33. The porous member 1050 is provided nearby theelastic wave generating device 3. A gap is provided to form a ink layer1060 between the elastic wave generating device 3 and the porous member1050.

The elastic wave generating device 3 detects the ink quantity orexistence of ink inside the subtank unit 33. In case of the presentembodiment, because the porous member 1050 is provided inside thesubtank unit 33, if the width of the ink layer 1060 becomes small, theelastic wave generating device 3 can detect the ink quantity only whenthe ink status is near to the ink end. However, ink does not wave insidethe container 1 because the porous member 1050 is provided inside thesubtank unit 33. Therefore, the elastic wave generating device 3 canaccurately detect the ink surface when the ink surface inside thesubtank unit 33 reaches to the lower end of the porous member 1050 andexits between the ink layer 1060. Moreover, the elastic wave generatingdevice 3 can detect the ink quantity and existence of ink inside thesubtank unit 33 accurately.

Moreover, because the elastic wave generating device 3 is providedinside the subtank unit 33, the elastic wave generating device 3 candetect the ink quantity and the existence of ink inside the subtank unit33 even when the ink inside the ink cartridge 180 is used up. Therefore,the ink jet recording apparatus can judge whether the printing processcan be continued or not.

The elastic wave generating device 3 and the porous member 1050 areprovided inside the container 1 of the ink cartridge in the embodimentshown in FIG. 91. Moreover, as shown in FIG. 91 and FIG. 92, the elasticwave generating device 3 and the porous member 1050 are also providedinside the subtank unit 33. Therefore, the elastic wave generatingdevice 3 and the porous member 1050 are provided on both of the inkcartridge shown in FIG. 91 and the subtank unit 33 shown in FIG. 92.However, the elastic wave generating device 3 and the porous member 1050can be provided to only one of the ink cartridge shown in FIG. 91 or thesubtank unit 33 shown in FIG. 92.

According to the embodiment shown in FIG. 93, if the ink absorbingmember 74 and 75 expose from the ink by consumption of ink inside thecontainer 1, ink contained in the ink absorbing member 74 and 75, whichis made from a porous material, flows out by the own weight and issupplied to the recording head 31. If ink is used up, the ink absorbingmember 74 and 75 absorbs the ink remained in the through hole 1 c, theink is thereby drained from the concave part of the through hole 1 c.Therefore, the condition of the reflective wave of the elastic wavegenerated by the elastic wave generating device 70 at the ink end statuschanges, and thus the timing of ink end status can be further accuratelydetected. Furthermore, the ink absorbing member 74 and 75 are designedsuch that the capillary force works in the ink absorbing member 74 and75 is equal to the capillary force which can hold ink or greater thanthe capillary force which can hold ink. The ink absorbing member 74 and75 thereby absorb ink remained in the through hole 1 c.

FIGS. 94(I)-94(V) show manufacturing methods of the elastic wavegenerating device 3, 15, 16 and 17. A base plate 20 is formed bymaterial such as the burning-endurable ceramic. Referring to FIG. 94(I),first of all, a conductive material layer 21 which becomes an electrodeat one side is formed on the base plate 20. Next, referring to FIG.94(II), a green sheet 22 serving as piezoelectric material is placed onthe conductive material layer 21. Next, referring to FIG. 94(III), thegreen sheet 22 is formed in a predetermined shape by a press processingor the like and is made into the form of a vibrator, and is air-dried.Thereafter, the burning is performed on the green sheet 22 at a burningtemperature of, for example, 1200° C. Next, referring to FIG. 94(IV), aconductive material layer 23 serving as other electrode is formed on thesurface of the green sheet 22 so as to be polarized in a capable offlexural-oscillation manner. Finally, referring to FIG. 94(V), the baseplate 20 is cut along each element. By fixing the base plate 20 in apredetermined face of the container 1 by use of adhesive or the like,the elastic wave generating device 3 can be fixed on the predeterminedface of the container and the ink cartridge is completed which has abuilt-in function which detects the ink remaining amount.

FIG. 95 shows another embodiment of the elastic wave generating device 3shown in FIG. 94. In the embodiment shown in FIG. 94, the conductivematerial layer 21 is used as a connecting electrode. On the other hand,in the embodiment shown in FIG. 95, connecting terminals 21 a and 23 aare formed by a solder in an upper position than the surface of thepiezoelectric material layer comprised of the green sheet 22. By theprovision of the connecting terminals 21 a and 23 a, the elastic wavegenerating device 3 can be directly mounted to the circuit board, sothat inefficient connection such as one by lead wires can be avoided.

Now, the elastic wave is a type of waves which can propagate throughgas, liquid and solid as medium. Thus, the wavelength, amplitude, phase,frequency, propagating direction and propagating velocity of the elasticwave change based on the change of medium in question. On the otherhand, the state and characteristic of the reflected wave of the elasticwave change according to the change of the medium. Thus, by utilizingthe reflected wave which changes based on the change of the mediumthrough which the elastic wave propagates, the state of the medium canbe observed. In a case where the state of the liquid inside the liquidcontainer is to be detected by this method, an elastic wavetransmitter-receiver will be used for example. Let us explain this byreferring to embodiments shown in FIGS. 90-91. First, thetransmitter-receiver gives out the elastic wave to the medium, forexample, the liquid or the liquid container. Then, the elastic wavepropagates through the medium and arrives at the surface of the liquid.Since a boundary is formed between the liquid and the gas on the liquidsurface, the reflected wave is returned to the transmitter-receiver. Thetransmitter-receiver receives the reflected wave. A distance between theliquid surface and a transmitter or receiver can be measured based on anoverall traveled time of the reflected wave, or a damping factor of theamplitudes of the elastic wave generated by the transmitter and thereflected wave reflected on the liquid surface, and soon. Utilizingthese, the state of the liquid inside the liquid container can bedetected. The elastic wave generating device 3 may be used as a singleunit of the transmitter-receiver in the method utilizing the reflectedwave based on the change of the medium through which the elastic wavepropagates, or a separately provided receiver may be mounted thereto.

As described above, in the elastic wave, generated by the elastic wavegenerating device 3, propagating through the ink liquid, the travelingtime of the reflected wave occurring on the ink liquid surface to arriveat the elastic wave generating device 3 varies depending on density ofthe ink liquid and the liquid level. Thus, if the composition of ink isfixed, the traveling time of the reflected wave which occurred in theink liquid surface varies depending on the ink amount. Therefore, theink amount can be detected by detecting the time period during which theelastic wave generating device 3 generates the elastic wave and then thewave reflected from the ink surface arrives at the elastic wavegenerating device 3. Moreover, the elastic wave vibrates particlescontained in the ink. Thus, in a case of using pigment-like ink whichuses pigment as a coloring agent, the elastic wave contributes toprevent precipitation of the pigment or the like.

By providing the elastic wave generating device 3 in the container 1,when the ink of the ink cartridge approaches (decreases to) an ink-endstate and the elastic wave generating device 3 can no longer receive thereflected wave, it is judged as an ink-near-end and thus can giveindication to replace the cartridge.

FIG. 96 shows an ink cartridge according to another embodiment of thepresent invention. Plural elastic wave generating device 41-44 areprovided on the side wall of the container 1, spaced at a variableinterval from one another in the vertical direction. In the inkcartridge shown in FIG. 96, whether or not the ink is present atmounting levels of respective elastic wave generating device 41-44 canbe detected by whether or not the ink is present at respective positionsof the elastic wave generating device 41-44. For example, suppose thatthe liquid level of ink is at a point between the elastic wavegenerating device 44 and 43. Then, the elastic wave generating device 44detects and judges that the ink is empty while the elastic wavegenerating device 41, 42 and 43 detect and judge respectively that theink is present. Thus, it can be known that the liquid level of ink liesin a level between the elastic wave generating device 44 and 43. Thus,provision of the plural elastic wave generating device 41-44 makespossible to detect the ink remaining amount in a step-by-step manner.

FIG. 97 and FIG. 98 show ink cartridges according to still anotherembodiments of the present invention. In an embodiment shown in FIG. 97,an elastic wave generating device 65 is mounted in a bottom face 1 aformed a slope in the vertical direction. In an embodiment shown in FIG.98, an elastic wave generating device 66 of an elongated shape in thevertical direction is provided in the vicinity of the bottom face of aside wall 1 b.

According to the embodiments shown in FIG. 97 and FIG. 98, when part ofthe elastic wave generating device 65 and 66 is exposed from the liquidsurface, the traveled time of the reflected wave and the acousticimpedance of the elastic waves generated by the elastic wave generatingdevice 65 continuously change corresponding to the change (Δh1, Δh2) ofthe liquid surface. Thus, the process from the ink-near-end state to theink-end state of ink remaining amount can be accurately detected bydetecting the degree of change in the traveled time of the reflectedwave or the acoustic impedance of the elastic waves.

Furthermore, a porous member 1050 is provided inside the container 1.The porous member 1050 prevents the waving and bubbling of ink insidethe container 1. The porous member 1050 thereby prevents the elasticwave generating device 65 and 66 to detects the ink existencemistakenly.

In the embodiment shown in FIG. 97, the porous member 1050 is providedin the container 1 such that the slope of the bottom face 1055 of theporous member 1050 is parallel to the slope of the elastic wavegenerating device 65. A gap is provided between the bottom face 1055 andthe elastic wave generating device 65 and forms a ink layer 1060.Therefore, as the embodiment shown in FIG. 90, when the ink surface inthe container 1 reaches to the lower end of the porous member 1050 andexists within the ink layer 1060, the elastic wave generating device 3can detect the ink surface accurately.

In the embodiment shown in FIG. 98, one side face of the porous member,not shown in the figure, is provided in the container 1 such that theone side face is parallel to the elastic wave generating device 66. Agap is provided between the one side face and the side wall 1 a. In thepresent embodiment, when ink is filled inside the container 1 and gapbetween the one side face of the porous member and the side wall 1 b,the reflective wave of the elastic wave generated by the elastic wavegenerating device 66 does not change. On the other hand, if ink insidethe container 1 is consumed, and the gap between the one side face ofthe porous member and the side wall 1 b arises, the reflective wave ofthe elastic wave generated by the elastic wave generating device 66gradually changes. Therefore, the elastic wave generating device 66 candetect the ink consumption status when the ink surface exists within theregion of the length Δh2 of the elastic wave generating device 66. Thelength of the elastic wave generating device 66 is not limited.

Though in the above embodiments a flexural oscillating typepiezoelectric vibrator is used so as to suppress the increase of thecartridge size, a vertically vibrating type piezoelectric vibrator mayalso be used. In the above embodiments, the elastic wave is transmittedand received by a same elastic wave generating device. In still anotherembodiment, the elastic wave generating device may be providedseparately as one for use in transmitting the elastic wave and other forreceiving the elastic wave, so as to detect the ink remaining amount.

FIG. 99 shows an ink cartridge according to still another embodiment ofthe present invention. Plural elastic wave generating device 65 a, 65 band 65 c on the bottom face 1 a formed a slope in the vertical directionspaced at an interval are provided in the container 1.

Furthermore, a porous member 1050 is provided inside the container 1. Agap is provided between the porous member 1050 and the elastic wavegenerating device 65 a, 65 b, and 65 c to form an ink layer 1060. Byproviding the porous member 1050 inside the container 1, the porousmember 1050 prevents the waving or bubbling of ink inside the container1 when the ink cartridge moves together with the recording head by thescanning operation during the printing process. Therefore, the bubble ofink is difficult to generate around the elastic wave generating device65 z, 65 b, and 65 c. Furthermore, even if the bubble of ink generates,because the porous member 1050 absorbs the bubble of ink, the bubbledoes not stay around the elastic wave generating device 65 a, 65 b, and65 c. The elastic wave generating device 65 a, 65 b, and 65 c canthereby accurately detect the ink consumption status.

The width of the ink layer 1060 is not limited as the embodiment t shownin FIG. 97.

According to the present embodiment, the arrival time (traveled time) ofthe reflected waves of the elastic waves to the respective elastic wavegenerating device 65 a, 65 b and 65 c in the respective mountingpositions of the elastic wave generating device 65 a, 65 b and 65 cdiffers depending on whether or not the ink is present in the respectivepositions of the plural elastic wave generating device 65 a, 65 b and 65c. Thus, whether or not the ink is present in the respective mountedposition levels of the elastic wave generating device 65 a, 65 b and 65c can be detected by scanning each elastic generating means (65 a, 65 band 65 c) and by detecting the traveled time of the reflected wave ofthe elastic wave in the elastic wave generating device 65 a, 65 b and 65c. Hence, the ink remaining amount can be detected in a step-by-stepmanner. For example, suppose that the liquid level of ink is at a pointbetween the elastic wave generating device 65 b and 65 c. Then, theelastic wave generating device 65 c detects and judges that the ink isempty while the elastic wave generating device 65 a and 65 b detect andjudge respectively that the ink is present. By overall evaluating theseresults, it becomes known that the liquid level of ink lies in a levelbetween the elastic wave generating device 65 b and 65 c.

FIGS. 100 and Fi. 101 show cross sections of the ink-jet recordingapparatus according to still another embodiment of the presentinvention.

FIG. 100 shows a cross section of the ink-jet recording apparatus alone.

FIG. 101 is a cross section of the ink-jet recording apparatus to whichthe ink cartridge 272 is mounted. A carriage 250 capable ofreciprocating in the direction of the width of the ink-jet recordingpaper includes a recording head 252 in a lower face thereof. Thecarriage 250 includes a subtank unit 256 in an upper face of therecording head 252. The subtank unit 256 has a similar structure to thatshown in FIG. 92. The subtank unit 256 has an ink supply needle 254facing an ink cartridge 272 mounting side. In the carriage 250, there isprovided a convex part 258 in a manner such that the convex part 258 isdisposed counter to a bottom portion of the ink cartridge 272 and in anarea where the ink cartridge 272 is to be mounted there above. Theconvex part 258 includes an elastic wave generating device 260 such asthe piezoelectric vibrator.

FIGS. 102 show an embodiment of the ink cartridge suitable for therecording apparatus shown in FIGS. 100.

FIG. 102 shows an embodiment of the ink cartridge for use with a singlecolor, for instance, the black color. The ink cartridge 272 according tothe present embodiment, comprises a container which houses ink and anink supply port 276 which comes in contact with an ink supply needle 254of the recording apparatus in a sealed manner. In the container 274,there is provided the concave part 278, positioned in a bottom face 274a, which is to be engaged with the convex part 258 shown in FIG. 101.The concave part 278 houses ultrasound transferring material such asgelated material 280.

The ink supply port 276 includes a packing ring 282, a valve body 286and a spring 284. The packing ring 282 is engaged with the ink supplyneedle 254 in a fluid-tight manner. The valve body 286 is constantly andelastically contacted against the packing ring 282 by way of the spring284. When the ink supply needle 254 is inserted to the ink supply port276, the valve body 286 is pressed by the ink supply needle 254 so as toopen an ink passage. On an upper wall of the container 274, there ismounted a semiconductor memory means 288 which stores data on ink insidethe ink cartridge and so on.

A porous member 1050 is provided inside the container 274. A gap isprovided between the porous member 1050 and the gelated material 280 toform an ink layer 1060. By providing the porous member 1050 inside thecontainer 274, the porous member 1050 prevents the waving or bubbling ofink inside the container 274. Therefore, the elastic wave generatingdevice 260 can accurately detect the ink consumption status as shown inFIG. 90.

As in the embodiment shown in FIG. 90, the present embodiment of theelastic wave generating device 260 can accurately detect the ink surfacewhen the ink surface inside the container 274 reaches to the lower endof the porous member 1050 and exists within the ink layer 1060. Thewidth of the gap between the porous member 1050 and the elastic wavegenerating device 260 is not limited. Preferably, the porous member 1050is provided vicinity of the elastic wave generating device 260.

Referring to FIG. 101, when the ink supply port 276 of the ink cartridge272 is inserted through the ink supply needle 254 of the subtank unit256, the valve body 286 recedes against the spring 284, so that an inkpassage is formed and the ink inside the ink cartridge 272 flows intothe ink chamber 262. At a stage where the ink chamber 262 is filled withink, a negative pressure is applied to a nozzle opening of the recordinghead 252 so as to fill the recording head with ink. Thereafter, therecording operation is performed. When the ink is consumed in therecording head 252 by the recording operation, a pressure in thedownstream of a flexible valve 266 decreases. Then, the flexible valve266 is positioned away from a valve body 270 so as to become opened.When the flexible valve 36 is opened, the ink in the ink chamber 262flows into the recording head 252 through the ink passage 35.Accompanied by the ink which has flowed into the recording head 252, theink in the ink cartridge 272 flows into the subtank unit 256.

While the recording apparatus is operating, a drive signal is suppliedto the elastic wave generating device 260 at a detection timing which isset in advance, for example, at a certain period of time. The elasticwave generated by the elastic wave generating device 260 is radiatedfrom the convex part 258 and is transferred to the ink inside the inkcartridge 272 by propagating through the gelated material 280 in thebottom face 274 a of the ink cartridge 272. Though the elastic wavegenerating device 260 is provided in the carriage 250 in FIGS. 101, theelastic wave generating device 260 may be provided inside the subtankunit 256.

Since the elastic wave generated by the elastic wave generating device260 propagates through the ink liquid, the traveling time of thereflected wave occurring on the ink liquid surface to arrive at theelastic wave generating device 260 varies depending on density of theink liquid and the liquid level. Thus, if the composition of ink isfixed, the traveling time of the reflected wave which occurred in theink liquid surface varies depending on the ink amount. Therefore, theink amount can be detected by detecting the time duration during whichthe reflected wave arrives at the elastic wave generating device 260from the ink liquid surface when the ink liquid surface is excited bythe elastic wave generating device 260. Moreover, the elastic wavegenerated by the elastic wave generating device 260 vibrates particlescontained in the ink. Thus, in a case of using pigment-like ink whichuses pigment as a coloring agent, the elastic wave contributes toprevent precipitation of the pigment or the like.

After the printing operation and maintenance operation or the like andwhen the ink of the ink cartridge approaches (decreases to) an ink-endstate and the elastic wave generating device 260 can no longer receivethe reflected wave even after the elastic wave generating device sendsout the elastic wave, it is judged that the ink is in an ink-near-endstate and thus this judgment can give indication to replace thecartridge anew. Moreover, when the ink cartridge 272 is not mountedproperly to the carriage 250, the shape of the elastic wave from theelastic generating means 260 changes in an extreme manner. Utilizingthis, warning can be given to a user in the event that the extremechange in the elastic wave is detected, so as to prompt the user tocheck on the ink cartridge 272.

The traveling time of the reflected wave of the elastic wave generatedby the elastic wave generating device 260 is affected by the density ofink housed in the container 274. Since the density of ink may differ bythe type of ink used, data on the types of ink are stored in asemiconductor memory means 288, so that a detection sequence can be setbased on the data and thus the ink remaining amount can be furtherprecisely detected.

FIG. 103 shows an ink cartridge 272 according to still anotherembodiment of the present invention. In the ink cartridge 272 shown inFIG. 103, the bottom face 274 a is formed a slope in the verticaldirection.

In the ink cartridge 272 shown in FIG. 103, when the ink remainingamount is becoming low and part of a radiating area of the elastic wavegenerating device 260 is exposed from the liquid surface, the traveledtime of the reflected wave of the elastic waves generated by the elasticwave generating device 260 continuously changes corresponding to thechange Δh1 of the liquid surface. The Δh1 denotes change of the heightof the bottom face 274 a in both ends of the gelated material 280. Thus,the process from the ink-near-end state to the ink-end state of inkremaining amount can be accurately detected by detecting the degree ofchange in the traveled time of the reflected wave of the elastic wavegenerating device 260.

Furthermore, a porous member 1050 is provided inside the container 274.The porous member 1050 prevents the waving or bubbling of ink inside thecontainer 274. Therefore, the elastic wave generating device 260 canaccurately detect the ink consumption status.

The porous member 1050 is provided in the container 274 such that theslope of the bottom face 1055 of the porous member 1050 is parallel tothe slope of the bottom face of the container 274. A gap is providedbetween the bottom face 1055 and the elastic wave generating device 260and forms a ink layer 1060.

When ink is filled inside the container 274 and ink layer 1060, thereflective wave of the elastic wave generated by the elastic wavegenerating device 260 does not change. On the other hand, if ink insidethe container 274 is consumed, gap arises in the ink layer 1060 insteadof ink. With the arising of the gap in the ink layer 1060, thereflective wave of the elastic wave generated by the elastic wavegenerating device 260 gradually changes. Therefore, the elastic wavegenerating device 260 can detect the ink quantity when the ink status inthe container 274 is near to ink end status. The width of the ink layer1060 is not limited as the embodiment shown in FIG. 97.

FIG. 104 shows an ink cartridge 272 and an ink-jet recording apparatusaccording to still another embodiment of the present invention. Theink-jet recording apparatus shown in FIG. 104 includes a convex part258′ in a side face 274 b in an ink supply port 276 side of the inkcartridge 272. The convex part 258′ includes an elastic wave generatingdevice 260′. Gelated material 280′ is provided in the side face 274 b ofthe ink cartridge 272 so as to engage with the convex part 258′.According to the ink cartridge 272 shown in FIG. 104, when the inkremaining amount is becoming low and part of a radiating area of theelastic wave generating device 260′ is exposed from the liquid surface,the traveled time of the reflected wave of the elastic waves generatedby the elastic wave generating device 260′ and the acoustic impedancecontinuously change corresponding to the change Δh2 of the liquidsurface. The Δh2 denotes difference in the height of both ends of thegelated material 280′. Thus, the process from the ink-near-end state tothe ink-end state of ink remaining amount can be accurately detected bydetecting the degree of change in the traveled time of the reflectedwave of the elastic wave generating device 260 or change in the acousticimpedance.

The ink cartridge according to the present embodiment further has aporous member 1050 provided inside the container 274. The ink-jetrecording apparatus includes a convex part 258′ in a side face 274 b inan ink supply port 276 side of the ink cartridge 272. The convex part258′ includes an elastic wave generating device 260′. The side face 1056of the porous member 1050 is parallel to the side face 274 b of thecontainer 274. An ink layer 1060 is formed on the gap between the sideface 1056 and the elastic wave generating device 260′.

The porous member 1050 prevents the waving or bubbling of ink inside thecontainer 274. Therefore, the elastic wave generating device 260′ canaccurately detect the ink consumption status.

When ink is filled inside the container 274 and ink layer 1060, thereflective wave of the elastic wave generated by the elastic wavegenerating device 260′ does not change. On the other hand, if ink insidethe container 274 is consumed, gap arises in the part corresponding tothe Δh2 which is a width in the height direction of the gelated material280′ within the ink layer 1060. With the arising of the gap in the inklayer 1060, the reflective wave of the elastic wave generated by theelastic wave generating device 260′ gradually changes. Therefore, theelastic wave generating device 260′ can detect the ink consumptionstatus when the is ink surface within the width Δh2 in the heightdirection.

If the ink surface is within the region of the Δh2, the elastic wavegenerating device 260′ can detect the ink surface. According to the inkcartridge according to the present embodiment, there is a gap betweenthe side face 1056 of the porous member 1050 and the elastic wavegenerating device 260′, the elastic wave generating device 260′ candetect the ink surface within the region of the Δh2 even if the porousmember 1050 is provided in the container 274. Therefore, by widen thewidth of the Δh2, the elastic wave generating device 260′ can detect theink surface when ink is filled in the container 274 until the inksurface when ink in the container 274 is nearly end.

In the above embodiments, the elastic wave is transmitted and receivedby the same elastic wave generating device 260 and 260′ when the inkremaining amount is detected based on the reflected wave at the liquidsurface. The present invention is not limited thereby and for example,as still another embodiment the elastic wave generating device 260 maybe provided separately as one for use in transmitting the elastic waveand other for receiving the elastic wave, so as to detect the inkremaining amount.

FIG. 105 is a cross sectional view of an embodiment of an ink cartridgefor use with a single color, for example, the black ink. The inkcartridge shown in FIG. 105 has a actuator 106. An ink supply port 2which comes in contact with an ink supply needle of the recordingapparatus in a sealed manner is provided in a container 1 which housesthe ink. In an outside portion of a bottom face 1 a of the container 1,the actuator 106 is mounted such that the actuator 106 can contact withink inside the container 1 via the through hole 1 c provided in thecontainer 1. In order that at a stage at which the ink K is almost usedup, i.e. at the time when the ink becomes an ink-end state, the statusaround the actuator 106 can change from the liquid to the gas, theactuator 106 is provided in a slightly upward position from the inksupply port 2. Moreover, an actuator 106 may be separately providedinstead, so that the actuator 106 is used as an means for detectingliquid only.

Furthermore, a porous member 1050 is provided inside the container 1.The porous member 1050 is provided around the actuator 106 inside thecontainer 1. A gap having a same depth with the through hole 1 c isprovided between the porous member 1050 and the actuator 106. Byproviding the porous member 1050 inside the container 1, the porousmember 1050 prevents the waving or bubbling of ink inside the container1 when the ink cartridge moves together with the recording head by thescanning operation during the printing process. Therefore, the bubble ofink is difficult to generate around the actuator 106. The actuator 106can thereby detect the ink consumption status accurately.

Moreover, the width of the gap between the porous member 1050 and theactuator 106 is not limited. To suppress the bubbling of ink as much aspossible, the width of ink layer 1060 is reduced by providing the porousmember 1050 on lower side of the container 1. If the width of the inklayer 1060 is small, the actuator 106 can detect the ink quantity onlywhen the ink status is near to the ink end. However, ink does not waveinside the container 1. Therefore, the actuator 106 can accuratelydetect the ink quantity when the ink consumption status is near to theink end status. Therefore, the porous member 1050 is preferably locatednearby the actuator 106 without limiting the width of gap between theporous member 1050 and the actuator 106.

Furthermore, the hole diameter of porous member 1050 is set such thatthe porous member 1050 does not absorbs ink existed in the through hole1 c before the ink surface reaches to the through hole 1 c. In otherwords, the porous member 1050 is designed such that the capillary forceworks in the porous member 1050 is smaller than the capillary forcewhich can hold ink in the container 1. Therefore, ink does not remain inthe porous member 1050 by its own weight and exists in the through hole1 c when the ink inside the container 1 is in an ink near end status.Furthermore, an airhole, not shown in the figure, is provided on thecontainer 1. The airhole is provided on the upper side of the container1 to communicate with outside of container 1. Air is introduced insidethe container 1 by the airhole, and ink flows downward by own weightwith advance of ink consumption. The residual ink thereby stays in thethrough hole 1 c.

On the other hand, the hold diameter of the porous member 1050 can beset such that the porous member 1050 absorbs ink existed in the throughhole 1 c when the predetermined amount of the ink is consumed. That is,the hole diameter of the porous member 1050 is set that the capillaryforce works in the porous member 1050 is equal to or larger than thecapillary force which can hold ink inside the container 1. The porousmember 1050 thereby absorbs ink existed in the through hole 1 c when thepredetermined amount of ink inside of the container 1 is consumed.Furthermore, the hole diameter of the porous member 1050 of a partnearby the ink supply port 2 is made smaller than the hole diameter ofthe other part of the porous member 1050. Ink existed in the throughhole 1 c is thereby absorbed by the porous member 1050 and furthersupplied to the ink supply port 2 from the porous member 1050.

For example, the hole diameter of the porous member 1050 is designedsuch that the porous member 1050 absorbs ink remained in the throughhole 1 c when the ink quantity in the ink cartridge becomes small amountin a degree that printing becomes defective. Furthermore, the holediameter of the porous member 1050 is designed such that the porousmember 1050 can send the ink, which is absorbed from the through hole 1c by the porous member 1050, to the ink supply port 2. The actuator 106can thereby detects the ink end accurately when the predetermined amountof ink is consumed and prevents the defective printing. Morespecifically, the hole diameter of the porous member 1050 nearby theactuator 106 is made larger than the hole diameter of the porous member1050 around the ink supply port 2.

The porous member 1050 occupies more than half of the volume of thecontainer 1. However, a relatively small porous member, not shown in thefigure, can be provided only around the actuator 106.

FIG. 106 is a cross sectional view of the bottom part of the inkcartridge of the present embodiment. The ink cartridge of the presentembodiment has a through hole 1 c on the bottom face 1 a of thecontainer 1, which contains ink. The bottom part of the through hole 1 cis closed by the actuator 650 and forms an ink storing part.

The ink cartridge according to the present embodiment has a porousmember 1050 provided inside the through hole 1 c. The porous member 1050thereby contacts with the vibrating region of the actuator 650. Byproviding the porous member 1050 to contact with the vibrating region ofthe actuator 650, ink does not remained in the through hole 1 c.

For example, the hole diameter of the porous member 1050 b providedaround the through hole 1 c is made smaller than the hole diameter ofthe porous member 1050 a provided inside the through hole 1 c. Thecapillary force of the porous member 1050 a around the through hole 1 cthereby becomes smaller than the capillary force of the porous member1050 a inside of the through hole 1 c. Therefore, ink contained in theporous member 1050 a inside the through hole 1 c is absorbed by theporous member 1050 b provided around the through hole 1 c when the inkinside the ink cartridge is consumed. Thus, ink does not remain in thethrough hole 1 c. Therefore, the accuracy of detecting the inkconsumption status inside the ink cartridge by the actuator 650 can beimproved.

FIG. 107 is a cross sectional view showing an embodiment of a major partof the ink-jet recording apparatus suitable for the ink cartridge shownin FIG. 105 and FIG. 106. A carriage 30 capable of reciprocating in thedirection of the width of the recording paper is equipped with a subtankunit 33, while the recording head 31 is provided in a lower face of thesubtank unit 33. Moreover, the ink supply needle 32 is provided in anink cartridge mounting face side of the subtank unit 33.

While the recording apparatus is operating, a drive signal is suppliedto the actuator 106 at a detection timing which is set in advance, forexample, at a certain period of time.

By adhering the actuator 106 to the container 1, a process of embeddingelectrodes for use in detecting the liquid surface is unnecessary in thecourse of forming the container 1. Therefore, an injection moldingprocess can be simplified and the leakage of the liquid from a place inwhich the electrodes are supposedly embedded can be avoided, thusimproving the reliability of the ink cartridge.

FIG. 108 is a cross sectional view of another embodiment of a subtankunit 33. The subtank unit 33 shown in FIG. 108 comprises the actuator106 and a porous member 1050. In the embodiment shown in FIG. 27, theactuator 106 and the porous member 1050 are provided in the container 1of the ink cartridge. However, as shown in FIG. 108, the actuator 106and the porous member 1050 can be provided inside the subtank unit 33.Furthermore, the actuator 106 and the porous member 1050 can be providedin both of inside the container 1 of the ink cartridge and the subtankunit 33.

According to the embodiment shown in FIG. 108, the actuator 106 candetect the ink quantity and the existence of ink inside the subtank unit33. Furthermore, the porous member 1050 can prevents the waving andbubbling of ink inside the subtank unit 33. Therefore, the actuator 106can accurately detects the ink quantity and the existence of ink.Moreover, because the actuator 106 is provided inside the subtank unit33, the actuator 106 can detect the ink quantity and the existence ofink inside the subtank unit 33 even when there is no ink inside the inkcartridge. The ink jet recording apparatus thereby can judges whetherthe printing operation can be continued or not.

If the actuator 106 and the porous member 1050 are provided on bothinside of the container 1 of the ink cartridge and the subtank unit 33,the actuator 106 can detect the ink consumption status more accurately.Furthermore, the actuator 106 can detect the timing of ink end insidethe container 1 of the ink cartridge.

FIG. 109 show ink cartridges according to still another embodiments ofthe present invention. In an embodiment shown in FIG. 109, a actuator106 is mounted in a bottom face 1 a formed a slope in the verticaldirection.

According to the embodiments shown in FIG. 109, when part of theactuator 106 is exposed from the liquid surface, the residual vibrationof the actuator 106 continuously changes. Therefore, the actuator 106can accurately detect the ink consumption quantity by detecting thechange of the acoustic impedance. For example, the actuator 106 candetect the ink surface while the ink surface exists within the region ofthe Δh1 shown in FIG. 109.

In the embodiment, the porous member 1050 is provided in the container1. The porous member 1050 prevents the waving and bubbling of ink insidethe container 1. The porous member 1050 thereby improves the accuracy ofdetecting the ink quantity by the actuator 106.

In the embodiment shown in FIG. 109, the porous member 1050 is providednearby the actuator 106. However, the present embodiment does notprovide the porous member 1050 inside the through hole 1 c. Therefore,ink directly contacts with the vibration region of the actuator 106.Thus, the vibration region of the actuator 106 exposed to air with theincrease in consumption of ink. Then, the vibration status at thevibration region of the actuator 106 changes. Therefore, to detect theink quantity by the actuator 106 becomes easy.

To suppress the waving and bubbling of ink as much as possible, it isnot preferable to have a gap between the porous member 1050 and theactuator 106. On the other hand, it is also not preferable that theporous member 1050 adhere to the vibrating region of the actuator 106 ina degree that the vibrating section of the actuator 106 cannot vibrate.Therefore, the porous member 1050 is preferable to provided around thevibrating region of the actuator 106. However, the porous member 1050can be contacts with the vibrating region of the actuator 106 if thevibrating region of the actuator 106 can vibrate and detect the inkexistence and the ink quantity.

FIG. 110 shows an ink cartridge according to still another embodiment ofthe present invention. Plural actuators 106 a, 106 b, and 106 c on thebottom face 1 a formed a slope in the vertical direction spaced at aninterval are provided in the container 1. Furthermore, a porous member1050 is provided inside the container 1. The porous member 1050 preventsthe actuators 106 a, 106 b, and 106 c to wrongly detect the inkconsumption status as explained in the FIG. 109.

According to the present embodiment, depends on whether the ink isexisted in the mounting position of each of the actuators 106 a, 106 b,and 106 c, the amplitude of the residual vibration and a resonantfrequency of the each of the actuators 106 a, 106 b, and 106 c differsat each of the mounting position of the actuators 106 a, 106 b, and 106c. Therefore, the existence of ink at the level of the mounting positionof each of the actuators 106 a, 106 b, and 106 c can be detected bymeasuring the counter electromotive force of the residual vibration ofeach of the actuators 106 a, 106 b, and 106 c. Therefore, residualquantity of ink can be detected step by step. For example, if the inksurface is at the level between the actuator 106 b and the actuator 106c, the actuator 106 a detects non-ink status, and the other actuators106 b and 106 c detects ink-exist status. By comprehensively judgingthese detecting results, it can be known that the ink surface positionsbetween the mounting position of the actuator 106 b and actuator 106 c.

FIG. 111 shows other embodiment of the through hole 1 c. In each ofFIGS. 111(A), (B), and (C), the left hand side of the figure shows thestatus that there is no ink K in the through hole 1 c, and the righthand side of the figure shows the status that ink K is remained in thethrough hole 1 c. In the embodiment of FIG. 28, the side face of thethrough hole 1 c is formed as the vertical wall. In FIG. 111(A), theside face 1 d of the through hole 1 c is slanted in vertical directionand opens with expanding to the outside. In FIG. 111(B), a steppedportion 1 e and 1 f are formed on the side face of the through hole 1 c.The stepped portion 1 f, which is provided above the stepped portion 1e, is wider than the stepped portion 1 e. In FIG. 111(C), the throughhole 1 c has a groove 1 g that extends to the direction in which ink iseasily discharged, that is, the direction to a ink supply port 2.

According to the shape of the through hole 1 c shown in FIG. 111(A) to(C), the quantity of ink K in the ink storing part can be reduced.Therefore, because the M′cav can be smaller than the M′max explained inFIG. 22 and FIG. 23, the vibration characteristic of the actuator 650 atthe time of the ink end status can be greatly different with thevibration characteristic when enough quantity of ink K for printing isremained in the container 1, and thus the ink end status can be reliablydetected.

Furthermore, in the ink cartridge of the present embodiment, a porousmember, not shown in FIG. 111, is provided around the through hole 1 cof the FIG. 111(A), FIG. 111(B), and FIG. 111(C). The porous member 1050becomes easy to absorb ink inside the through hole 1 c by forming theside face 1 d, stepped portion 1 e, and 1 f, or groove 1 g.

FIG. 112 is a slant view of the further other embodiment of theactuator. In this embodiment, the actuator 670 comprises a concave partforming base plate 80 and a piezoelectric element 82. The concave part81 is formed on the one side of the face of the concave part formingbase plate 80 by the technique such as etching, and piezoelectricelement 82 is mounted on the other side of the face of the concave partforming base plate 80. The bottom portion of the concave part 81operates as a vibrating region within the concave part forming baseplate 80. Therefore, the vibrating region of the actuator 670 isdetermined by the periphery of the concave part 81. Furthermore, theactuator 670 has the similar structure with the structure of theactuator 106 shown in FIG. 22, in which the base plate 178 and thevibrating plate 176 is formed as one body. Therefore, the manufacturingprocess during the manufacturing an ink cartridge can be reduced, andthe cost for manufacturing an ink cartridge also can be reduced. Theactuator 670 has a size which can be embedded into the through hole 1 cprovided on the container 1. By this embedding process, the concave part81 can operates as the cavity. The actuator 106 shown in FIG. 22 can beformed to be embedded into through hole 1 c as actuator 670 shown inFIG. 112. Furthermore, a porous member 1050 is provided around theactuator 670.

The actuator 106 of the ink cartridge 180B shown in FIG. 113 is mountedon the side wall of the supply port of the ink container 194. Theactuator 106 can be mounted on the side wall or bottom face of the inkcontainer 194 if the actuator 106 is mounted nearby the ink supply port187. The actuator 106 is preferably mounted on the center of the widthdirection of the ink container 194. Because ink is supplied to theoutside through the ink supply port 187, ink and actuator 106 reliablycontacts until the timing of the ink near end by providing the actuator106 nearby the ink supply port 187. Therefore, the actuator 106 canreliably detect the timing of the ink near end. A porous member 1050 isprovided around the actuator 106. The porous member 1050 prevents thewaving and the bubbling of ink and thereby prevents the actuator 106 towrongly detect the ink consumption status.

Furthermore, by providing the actuator 106 nearby the ink supply port187, the setting position of the actuator 106 to the connection point onthe carriage on the ink container becomes reliable during the mountingof the ink container on the cartridge holder of the carriage. It isbecause the reliability of coupling between the ink supply port with theink supply needle is most important during the coupling of the inkcontainer and the carriage. If there is even a small gap, the tip of theink supply needle will be hurt or a sealing structure such as O-ringwill be damaged so that the ink will be leaked. To prevent this kind ofproblems, the ink jet printer usually has a special structure that canaccurately positioning the ink container during the mounting of the inkcontainer on the carriage. Therefore, the positioning of the actuator106 becomes reliable by arranging the actuator nearby the ink supplyport. Furthermore, the actuator 106 can be further reliably positionedby mounting the actuator 106 at the center of the width direction of theink container 194. It is because the rolling is the smallest when theink container rolls along an axis, the center of which is center line ofthe width direction, during the mounting of the ink container on theholder.

FIG. 114 shows further other embodiment of the ink cartridge 180. FIG.114 shows a cross section of an ink cartridge 180C. The semiconductormemory device 7 and the actuator 106 are formed on the same circuitboard 610 in the ink cartridge 180C.

FIG. 115 shows further other embodiment of the ink cartridge 180. Aplurality of actuators 106 is mounted on the side wall 194 b of the inkcontainer 194 in the ink cartridge 180D shown in FIG. 115. It ispreferable to use the plurality of the actuators 106 which is formed inone body as shown in FIG. 26 for these plurality of actuators 106. Theplurality of actuators 106 is arranged on the side wall 194 b withinterval in vertical direction. By arranging the plurality of actuators106 on the side wall 194 b with interval in vertical direction, theresidual quantity of ink can be detected step by step.

The ink cartridge 180E shown in FIG. 115 mounts a actuator 606 which islong in vertical direction on the side wall 194 b of the ink container194. The change of the residual quantity of ink inside the ink container194 can be detected continuously by the actuator 606 which is long invertical direction. The length of the actuator 606 is preferably longerthan the half of the height of the side wall 194 b. In FIG. 115, theactuator 606 has the length from the substantially from the top end tothe bottom end of the side wall 194 b.

The ink cartridge 180F shown in FIG. 115 mounts a plurality of actuators106 on the side wall 194 b of the ink container 194 as the ink cartridge180D shown in FIG. 115. The ink cartridge 180F further comprises thewave preventing wall 192, which is long in vertical direction, along theside wall 194 b with predetermined space with the side wall 194 b suchthat the wave preventing wall 192 faces directly to the plurality ofactuators 106. It is preferable to use the plurality of the actuators106 which is formed in one body as shown in FIG. 26 for these pluralityof actuators 106. A gap which is filled with ink is formed between theactuator 106 and the wave preventing wall 192. Moreover, the gap betweenthe wave preventing wall 192 and the actuator 106 has a space such thatthe gap does not hold ink by capillary force. When the ink container 194is rolled, ink wave is generated inside the ink container 194 by therolling, and there is possibility that the actuator 106 malfunctions bydetecting gas or an air bubble caused by the shock of the ink wave. Byproviding the wave preventing wall 192, ink wave around the actuator 106can be prevented so that the malfunction of the actuator 106 can beprevented. The wave preventing wall 192 also prevents the air bubblegenerated by the rolling of ink to enter to the actuator 106.

Furthermore, a porous member 1050 is provided around the actuator 106 inthe embodiments shown in FIG. 115(A), FIG. 115(B), and FIG. 115(C). Theporous member 1050 prevents the waving or bubbling of ink and preventsthe actuator 106 to wrongly detect the ink consumption status.

The embodiment that the actuator 106 is mounted on an ink cartridge or acarriage, in which the ink cartridge is a separate body with thecarriage and mounted on the carriage, has been explained above. However,the actuator 106 can be mounted on the ink tank which is mounted on theink jet recording apparatus together with a carriage and formed togetherwith a carriage as one body. Furthermore, the actuator 106 can bemounted on the ink tank of the off-carriage type. The off-carriage typeink tank is a separate body with a carriage and supplies ink to carriagethrough such as tube. Moreover, the actuator of the present embodimentcan be mounted on the ink cartridge constituted so that a recording headand an ink container are formed as on body and possible to be exchanged.

Although the present invention has been described by way of exemplaryembodiments, it should be understood that many changes and substitutionsmay be made by those skilled in the art without departing from thespirit and the scope of the present invention which is defined only bythe appended claims.

The liquid container according to the present invention can reliablydetect a liquid consumption status and dispense with a complicatedsealing structure.

The liquid container according to the present invention can prevent thewaving or bubbling of liquid around the piezoelectric device.

Furthermore, the liquid container according to the present invention hasa piezoelectric device which can reliably detect a liquid consumptionstatus by detecting the liquid surface even in the case that liquidinside the liquid container waves and bubbles.

Furthermore, the liquid container according to the present invention canreliably detect a liquid consumption status in the liquid container evenif the piezoelectric device is mounted on the upper side of the liquidsurface in the liquid container.

Furthermore, the liquid container according to the present invention canreliably detect a liquid consumption status in the liquid container evenif the piezoelectric device is mounted on the top wall which is locatedabove the liquid surface in the liquid container. Therefore, the degreeof freedom to design the mounting position of the piezoelectric devicecan be increased.

Furthermore, the liquid container according to the present invention canreliably detect a liquid consumption status in the liquid container byreducing the amount of liquid remained inside of a cavity after theconsumption of the liquid inside the liquid container.

1. A liquid container comprising: a housing containing therein liquid; aliquid supply opening supplying liquid to an exterior of said housing; adetection device mounted on said housing, said detection devicecomprising a piezoelectric element for detecting a liquid consumptionstatus; and a wave absorbing wall extending in an interior of saidhousing disposed at a place facing said detection device; wherein theliquid container does not include a porous member in contact with theliquid.
 2. The liquid container according to claim 1, wherein a gap isdefined between said detection device and said wave absorbing wall. 3.The liquid container according to claim 2, wherein maid gap does notgenerate a capillary force for holding the liquid.
 4. The liquidcontainer according to claim 2, wherein said gap generates a capillaryforce which is smaller than a force for holding the liquid.
 5. Theliquid container according to claim 1, wherein said detection devicecomprises a cavity for contacting liquid, said cavity being formed toopen toward the interior of said housing.
 6. The liquid containeraccording to claim 1, wherein said wave absorbing wall in secured to andextends from an interior wall of said housing.
 7. The liquid containeraccording to claim 1, wherein said detection device is attached to afirst wall of said housing which extends in a vertical direction of theliquid level, and said wave absorbing wall extends in parallel with saidfirst wall of said housing.
 8. The liquid container according to claim1, wherein said detection device is attached to a bottom wall of saidhousing, and said wave absorbing wall extends in parallel with theliquid level.
 9. The liquid container according to claim 1, wherein saidwave absorbing wall extends in an inclined direction with respect to theliquid level.
 10. The liquid container according to claim 1, whereinsaid wave absorbing wall extends from a side wall of said housing whichis perpendicular to the liquid level.
 11. The liquid container accordingto claim 1, wherein said a capillary force is generated between at leasta part of said wave absorbing wall and an inner wall of said housing.12. The liquid container according to claim 1, wherein said waveabsorbing wall comprises a bending section which is formed by bending atleast a part of an edge of said wave absorbing wall toward a wall onwhich said detection device is mounted, and a gap defined by saidbending section and said detection device generates a capillary forcewhile a gap defined by said wave absorbing well and said detectiondevice does not generate a capillary force.
 13. The liquid containeraccording to claim 1, wherein said wave absorbing wall comprises aplurality of wave absorbing wall pieces, and at least one of saidplurality of wave absorbing wall pieces extends from a side wall of saidhousing which is perpendicular to the liquid level.
 14. The liquidcontainer according to claim 1, wherein said detection device comprisesa vibrating section which generates a counter electromotive force inaccordance with a residual vibration of said vibrating section.
 15. Theliquid container according to claim 1, wherein the liquid container ismounted on an ink-jet printing apparatus having a printhead which ejectsink droplets, and the liquid container supplies the liquid containedtherein to the printhead through said liquid supply opening.
 16. Aliquid container comprising: a housing containing therein liquid; aliquid supply opening supplying liquid to an exterior of said housing; adetection device mounted on said housing, said detection devicecomprising a piezoelectric element for detecting a liquid consumptionstatus; and a wave absorbing wall extending in an interior of saidhousing disposed at a place facing said detection device; wherein a gapis defined bewteen said detection device and said wave absorbing wall,and wherein said gap does not generate a capillary force for holding theliquid.
 17. A liquid container comprising: a housing containing thereinliquid; a liquid supply opening supplying liquid to an exterior of saidhousing; a detection device mounted on said housing, said detectiondevice comprising a piezoelectric element for *detecting a liquidconsumption status; and a wave absorbing wall extending in an interiorof said housing disposed at a place facing said detection device;wherein said detection device comprises a cavity for contacting liquid,said cavity being formed to open toward the interior of said housing.